1038/npp 2010 200; published online 15 December 2010″

1038/npp.2010.200; published online 15 December 2010″
“Type III interferons ([IFNs]IFN-lambda and interleukin-28 and -29 [IL-28/29]) are recently recognized cytokines with innate antiviral effects similar buy Combretastatin A4 to those of type I IFNs (IFN-alpha/beta). Like IFN-alpha/beta, IFN-lambda-expression can be induced by viruses, and it is believed that type I and III IFNs are regulated in the same manner. Hantaviruses are weak IFN-alpha/beta inducers and have surprisingly been

shown to activate IFN-alpha/beta-independent IFN-stimulated gene (ISG) expression. Here, we show that in Hantaan virus (HTNV)-infected human epithelial A549 cells, induction of IFN-lambda 1 preceded induction of MxA and IFN-beta by 12 and 24 h, respectively, Selleck AZD1480 and IFN-alpha was not induced at all. Furthermore, induction of

IFN-lambda 1 and MxA was observed in HTNV-infected African green monkey epithelial Vero E6 cells, a cell line that cannot produce type I IFNs, clearly showing that HTNV can induce IFN-lambda 1 and ISGs in the complete absence of IFN-alpha/beta. In HTNV-infected human fibroblast MRC-5 cells, which lack the IFN-lambda receptor, induction of MxA coincided in time with IFN-beta-induction. UV-inactivated HTNV did not induce any IFNs or MxA in any cell line, showing that activation of IFN-lambda 1 is dependent on replicating virus. Induction of both IFN-beta and IFN-lambda 1 in A549 cells after poly(I:C)-stimulation was strongly inhibited in HTNV-infected cells, suggesting that HTNV can inhibit signaling pathways used to simultaneously activate types I and III IFNs. In conclusion, we show that HTNV can cause type I IFN-independent IFN-lambda 1 induction and IFN-lambda 1-specific ISG induction.

Importantly, the results suggest the existence of specific signaling pathways that induce IFN-lambda 1 without simultaneous type I IFN induction during virus infection.”
“The dopamine receptor D2 (encoded by DRD2) is implicated in susceptibility to mental disorders and cocaine abuse, but mechanisms responsible for this relationship remain uncertain. DRD2 mRNA exists in two main splice isoforms with distinct functions: D2 long (D2L) and D2 short (D2S, lacking exon 6), expressed mainly postsynaptically and presynaptically, respectively. Two intronic single-nucleotide Immune system polymorphisms (SNPs rs2283265 (intron 5) and rs1076560 (intron 6)) in high linkage disequilibrium (LD) with each other have been reported to alter D2S/D2L splicing and several behavioral traits in human subjects, such as memory processing. To assess the role of DRD2 variants in cocaine abuse, we measured levels of D2S and D2L mRNA in human brain autopsy tissues (prefrontal cortex and putamen) obtained from cocaine abusers and controls, and genotyped a panel of DRD2 SNPs (119 abusers and 95 controls). Robust effects of rs2283265 and rs1076560 on reducing formation of D2S relative to D2L were confirmed.

However, it is still unknown whether both are involved in the reg

However, it is still unknown whether both are involved in the regulation of https://www.selleckchem.com/products/selonsertib-gs-4997.html production and/or release of VP. Na-x is the cerebral Na+-level sensor and Na-x-knockout mice do

not stop ingesting salt even when dehydrated. Here we examined VP production/release in Na-x-knockout mice, and found that they are normal in the VP response to dehydration or intraperitoneal-administration with hypertonic saline. In situ hybridization using an intron-specific probe showed that VP gene expression in the SON did not differ from wildtype mice when dehydrated. Also, there was no significant difference in the activity of subfornical organ neurons projecting to the SON between the two genotypes when stimulated by water deprivation. Furthermore, Na-x-knockout mice showed a normal response in urine excretion to dehydration. All these results indicate that the information of Na+-level increase detected by Na-x does not contribute to the control of VP production/release. (C) 2010 Elsevier Ireland Ltd. All rights reserved.”

efflux pumps located at the blood-brain barrier (BBB) prevent drugs entering the brain. As such, efflux pumps are a major obstacle to drug brain distribution. Amyotrophic lateral Selleckchem Nocodazole sclerosis (ALS) is a fatal neurodegenerative disease with little therapeutics available: riluzole is the only drug approved in its treatment. The lack of response to treatment in ALS may be, at least in part, due to increased activities of efflux pumps in relation to disease, leading to subtherapeutic brain concentrations of drugs. In the present study, we used a transgenic mouse model of ALS (G86R mSOD1 mice) to test this hypothesis. Expression and functionality of P-glycoprotein (ABCB1, P-gp) and Breast Cancer Resistance Protein (ABCG2, BCRP), two major efflux pumps, were studied. We observed an increased P-gp expression (1.5-fold) in presymptomatic mSOD1 mice compared to wild-type controls. Consistent with this, P-gp function

was also increased by 1.5-fold and riluzole brain disposition was decreased by 1.7-fold in mSOD1 mice. Contrasting with this, BCRP expression and function were unaltered by the pathology. These results demonstrate that BBB transport proteins are Cyclin-dependent kinase 3 modified in G86R mSOD1 mice ALS model. Such findings underline potential problems in extrapolating the results of animal studies to humans and developing clinical trials, especially for drugs transported by P-gp. (C) 2010 Elsevier Ireland Ltd. All rights reserved.”
“A vector based on Semliki Forest virus (SFV) expressing high levels of interleukin-12 (SFV-enhIL-12) has previously demonstrated potent antitumoral efficacy in small rodents with hepatocellular carcinoma (HCC) induced by transplantation of tumor cells. In the present study, the infectivity and antitumoral/antiviral effects of SFV vectors were evaluated in the clinically more relevant woodchuck model, in which primary HCC is induced by chronic infection with woodchuck hepatitis virus (WHV).

86) Nociceptin/orphanin FQ potency was enhanced in slices prepar

86). Nociceptin/orphanin FQ potency was enhanced in slices prepared from rats previously subjected to a 15 min swim stress (EC50 = 1.98 +/- 0.11 nM). Swim stress did not change the number or affinity of NOP receptors in DRN. Stress-elicited potentiation involved corticotropin-releasing factor (CRF)(1) receptors, GABA signaling and protein synthesis, being attenuated by pre-treatment with antalarmin (20 mg/kg, i.p.), diazepam (2.4 mg/kg, see more i.p.) and

cycloheximide (2.5 mg/kg, i.p.), respectively. In anesthetized unstressed rats, locally applied nociceptin/orphanin FQ(0.03 and 0.1 ng/30 nl) inhibited the firing rate of DRN neurons (to 80 +/- 7 and 54 +/- 10% of baseline, respectively). Nociceptin/orphanin FQ inhibition was potentiated both 24 h after swim stress and I h after CRF (30 ng/30 nl intra-DRN). Stress-induced potentiation was prevented by the selective CRF(1) receptor antagonist, NBI 30755 (20 mg/kg, i.p.). In contrast, the inhibitory response of DRN neurons to the 5HT(1A) agonist, 8CH-DPAT (1 mu g/1 mu l, intra-DRN) was not potentiated by swim stress, ruling out a nonspecific enhanced permeability of GIRK channel. Together, these findings suggest that CRF buy S63845 and the nociceptin/orphanin FQ/NOP system interact in the DRN during stress to control

5HT transmission: this may play a role in stress-related neuropsychopathologies. (C) 2009 Elsevier Ltd. All rights reserved.”
“Background: It has been widely accepted that glial pathology and disturbed synaptic transmission contribute to the neurobiology of depression. Apart from monoaminergic alterations, an influence of glutamatergic signal transduction has been reported. Therefore, gene expression of glutamate transporters that strictly control synaptic glutamate concentrations have to be assessed out in animal models of stress and depression.

Methods: We performed in situ-hybridizations in learned helplessness rats, a well established animal model of depression, to assess vGluT1 and

EAAT1-4. Sprague-Dawley rats of two inbred lines were tested for helpless behavior and grouped into three cohorts according to the number of failures to stop foot shock currents by lever pressing.

Results: Helpless animals showed a significantly suppressed expression of the glial glutamate transporter EAAT2 (rodent nomenclature GLT1) in hippocampus and cerebral cortex compared to littermates with low failure rate and not helpless animals. This finding was validated on protein level using immunohistochemistry. Additionally, expression levels of EAAT4 and the vesicular transporter vGluT1 were reduced in helpless animals. In contrast, the transcript levels of EAAT1 (GLAST) and EAAT3 (EAAC1) were not significantly altered.

Conclusions: These results strongly suggest reduced astroglial glutamate uptake and implicate increased glutamate levels in learned helplessness.

By virtue of genetic engineering it is possible to transfer genes

By virtue of genetic engineering it is possible to transfer genes involved in Cd tolerance or accumulation in high biomass plants. Nevertheless, the genetic determinants of Cd hyperaccumulation 4SC-202 molecular weight are far from being understood. It is thus indispensable to acquire more knowledge about these processes. Among Cd hyperaccumulators, Arabidopsis halleri (some populations can hyperaccumulate Cd) is considered as a model species for the study of metal homeostasis and detoxification. This review will summarize our knowledge about Cd tolerance and

accumulation acquired in A. halleri and how this knowledge may be used in phytoextraction.”
“We present a schizophrenia association study using an extensive linkage disequilibrium (LD) mapping approach in seven candidate genes with a well established link to dopamine, including receptors (DRD2, DRD3) and genes involved in its metabolism and transport (ACE, COMT, DAT, MAO-A,

MAO-B). The sample included 242 subjects JQ-EZ-05 diagnosed with schizophrenia and related disorders and 373 hospital-based controls. 84 tag SNPs in candidate genes were genotyped. After extensive data cleaning 70 SNPs were analyzed for association of single markers and haplotypes. One block of four SNPs (rs165849, rs2518823, rs887199 and rs2239395) in the 31 downstream region of the COMT gene which included a non-dopaminergic candidate gene, the ARVCF (Armadillo like VeloCardio Facial) gene, was associated

with the risk of schizophrenia. The genetic region including the ARVCF gene in the 22q11.21 chromosome is associated Acyl CoA dehydrogenase with schizophrenia in a Spanish series. Our results will assist in the interpretation of the controversy generated by genetic associations of COMT and schizophrenia, which could be the result of different LD patterns between COMT markers and the 3′ region of the ARVCF gene. (C) 2009 Elsevier Inc. All rights reserved.”
“It is known that even if a ligand peptide is designed to bind to a target receptor on the surface of a pathogen such as viruses, bacteria or cancer cells, it is likely that some receptors are subject to random mutation and thus the ligand has a reduced ability to bind to these receptors. This issue is known as drug-resistant or escape mutants. In this paper, we present an idea to inhibit the evolving receptors by using an ensemble of all possible single- or double-point mutant sequences of the ligand peptide. Several mutant ligands in the ensemble are expected to bind to the mutant receptors, and then the ensemble may create a defensive wall surrounding the target receptors in receptor-sequence space. We examined the effectiveness of this “”evolutionary containment”" of the evolving receptors through eight peptide-protein complex systems, which were retrieved from the Protein Data Bank (PDB).

The VMR was decreased to 1332 4 +/- 353 9 from control of 2886 5

The VMR was decreased to 1332.4 +/- 353.9 from control of 2886.5 +/- 692.2 spikes/distension (n=6, P<0.01) following MPEP (10 mu mol/kg, iv). Utilizing the isolated mouse bladder/pelvic nerve preparation, we

found that neither MPEP (up to 3 mu M) nor MTEP (up to 10 mu M) affected Nutlin3a afferent discharge in response to bladder distension (n=4-6). In contrast, MPEP attenuated the responses of the mesenteric nerves to distension of the mouse jejunum in vitro. These data suggest that mGlu5 receptors play facilitatory roles in the processing of afferent input from the urinary bladder, and that central rather than peripheral mGlu5 receptors appear to be responsible. (c) 2008 Elsevier Ireland Ltd. All rights reserved.”
“Background. Fatigue is a common complaint among older adults, but the association JQ1 cost of fatigue with subsequent function is not well known.

Methods. This 3-year longitudinal study of older primary care patients evaluates the association of fatigue, operationalized as feeling tired most of the time, with functional status at baseline and over time.

Results. After adjustment for multiple potential confounders, participants who were tired at baseline had worse Short Form-36 Physical

Performance Index scores, activity of daily living scores, and gait speeds. These functional deficits persisted throughout the follow-up period.

Conclusions. Fatigue in older adults is associated with functional deficits that persist for years. Further research is needed to understand the causes of fatigue and to develop specific treatments for this serious symptom.”
“To date, there has been no report clarifying the existence of sensory nerve fibers as the origin of the hip tuclazepam joint pain of osteoarthritis. We examined the existence of sensory

nerve fibers in osteoarthritis (OA), osteonecrosis of the femoral head (ONFH), and femoral neck fracture of the human hip joint. Ten labra of 10 human hip joints were harvested during a total hip arthroplasty. Each labrum was separated into 12 sections and we used three sections for analysis, which included 2 weight-bearing and 1 non-weight-bearing portion. Protein gene product 9.5 (PGP 9.5) immunoreactive sensory nerve fibers were found in the labrum and synovium harvested from the weight-bearing portion in the OA group. Some of these sensory nerve fibers were also positive for turnout necrosis factor alpha (TNF). The PGP 9.5 immunoreactive sensory nerve fibers existed in the labrum tissue and inflammatory TNF positive cells were observed ill the hyperplastic synovium. On the other hand, we Could not demonstrate PGP 9.5 or TNF immunoreactive sensory nerve fibers and cells in any of the ONFH group Or the non-weight-bearing portion in the OA group.

In contrast, the W27A mutation precluded portal-scaffold interact

In contrast, the W27A mutation precluded portal-scaffold interactions in infected cell lysates, reduced the solubility of pU(L)6, decreased incorporation of the portal into capsids, GDC-0068 research buy and abrogated viral-DNA cleavage and packaging.”
“Some human herpesviruses (HHV) are etiological contributors to a wide range of malignant diseases. These HHV express latent membrane proteins (LMPs), which are type III membrane proteins consistently exposed at

the cell surface in these malignancies. These LMPs have relatively large cytoplasmic domains but only short extracellular loops connecting transmembrane segments that are accessible at the surface of infected cells, but they do not elicit antibodies in the course of natural infection and tumorigenesis. We report here that conformational peptides mimicking two adjacent loops of the Epstein-Barr virus (EBV) LMP1 (2LS peptides) induce high-affinity antibodies with remarkable antitumor activities in mice. In active immunization experiments, LMP1-targeting 2LS vaccine conferred tumor protection in BALB/c mice. Moreover, this tumor protection is dependent

upon a humoral anti-2LS immune response as demonstrated in DO11.10 (TCR-OVA) mice challenged with LMP1-expressing tumor and in SCID mice xenografted with human EBV-positive lymphoma cells. These data provide a proof of concept for 2LS immunization against short external loops of viral LMPs. This approach might Rucaparib research buy possibly be extended to other infectious agents expressing type III membrane proteins.”
“Viruses often evolve resistance to antiviral agents. While resistant KPT-330 nmr strains are able to replicate in the presence of the agent, they generally exhibit lower fitness than the wild-type strain in the absence of the inhibitor. In some cases, resistant strains become dependent on the antiviral agent. However, the agent rarely, if ever, elevates dependent strain fitness above the uninhibited wild-type level. This would require an adaptive mechanism to convert the antiviral agent into a beneficial growth

factor. Using an inhibitory scaffolding protein that specifically blocks phi X174 capsid assembly, we demonstrate that such mechanisms are possible. To obtain the quintuple-mutant resistant strain, the wild-type virus was propagated for approximately 150 viral life cycles in the presence of increasing concentrations of the inhibitory protein. The expression of the inhibitory protein elevated the strain’s fitness significantly above the uninhibited wild-type level. Thus, selecting for resistance coselected for dependency, which was characterized and found to operate on the level of capsid nucleation. To the best of our knowledge, this is the first report of a virus evolving a mechanism to productively utilize an antiviral agent to stimulate its fitness above the uninhibited wild-type level.

“Environmental proteomics, also referred to as metaproteom

“Environmental proteomics, also referred to as metaproteomics, is an emerging technology to study the structure and function of microbial communities. Here, we applied semi-quantitative label-free proteomics using one-dimensional gel electrophoresis combined with LC-MS/MS and normalized

spectral counting together with fluorescence in situ hybridization and confocal laser scanning microscopy to characterize the metaproteome of the lung lichen symbiosis Lobaria pulmonaria. In addition to the myco- BMS202 mouse and photobiont, L. pulmonaria harbors proteins from a highly diverse prokaryotic community, which is dominated by Proteobacteria and including also Archaea. While fungal proteins are most dominant (75.4% of all assigned spectra), about the same amount of spectra were assigned to prokaryotic proteins (10%)

and to the green algal photobiont (9%). While the latter proteins were found to be mainly associated with energy and carbohydrate metabolism, a major proportion of fungal and bacterial proteins appeared to be involved in PTMs and protein turnover and other diverse functions.”
“Due to the lack of precise markers indicative of its occurrence and progression, coronary artery disease (CAD), the most common type of heart diseases, is currently associated with high mortality in the United States. To systemically identify novel protein biomarkers associated with CAD progression for early diagnosis and possible therapeutic

intervention, we employed an iTRAQ-based quantitative proteomic approach to analyze the proteome changes in Selleck Gilteritinib the plasma collected from a pair Lck of wild-type versus apolipoprotein E knockout (APOE(-/-)) mice which were fed with a high fat diet. In a multiplex manner, iTRAQ serves as the quantitative ‘in-spectra’ marker for ‘cross-sample’ comparisons to determine the differentially expressed/secreted proteins caused by APOE knock-out. To obtain the most comprehensive proteomic data sets from this CAD-associated mouse model, we applied both MALDI and ESI-based mass spectrometric (MS) platforms coupled with two different schemes of multidimensional liquid chromatography (2-D LC) separation. We then comparatively analyzed a series of the plasma samples collected at 6 and 12wk of age after the mice were fed with fat diets, where the 6- or 12-wk time point represents the early or intermediate phase of the fat-induced CAD, respectively. We then categorized those proteins showing abundance changes in accordance with APOE depletion. Several proteins such as the gamma and beta chains of fibrinogen, apolipoprotein B, apolipoprotein C-I, and thrombospondin-4 were among the previously known CAD markers identified by other methods. Our results suggested that these unbiased proteomic methods are both feasible and a practical means of discovering potential biomarkers associated with CAD progression.

Collectively, these data suggest a

Collectively, these data suggest a AZD1480 purchase hitherto unrecognized association between neutrophil activation, pathogenesis, and the development of DSS and point to future strategies for guiding prognosis.”
“The high rate of HIV-1 evolution contributes to immune escape, enables the virus to escape drug therapy, and may underlie the difficulty of producing an effective vaccine. Identifying constraints

on HIV evolution is therefore of prime importance. To investigate this problem, we examined the relationships between sequence diversity, selection, and protein structure. We found that while there was an increase in sequence diversity over time,

this variation MK5108 had a tendency to be limited to specific structural regions. When individual sites were analyzed, there was, in contrast, substantial and widespread evolutionary constraint over gag and env. This constraint was present even in the highly variable envelope proteins. The evolutionary significance of an individual site is indicated by the change in selection pressure along the time course: increasing entropy indicates that the site is evolving predominantly in a more “”clock”"-like manner, low entropy values with no increase indicate a high degree of constraint, and high entropy values indicate a lack of constraint. Few sites display high degrees of turnover. Mapping these sites onto the three-dimensional protein structure, we found a significant difference between evolutionary rates for regions buried in the core of the protein and those on the surface. This constraint did not change over the time period analyzed and was not subtype dependent, as similar results were found for subtypes B and C. This link between sequence and structure not only demonstrates the limits of recent HIV-1 evolution but also highlights the

only origins of evolutionary constraint on viral change.”
“Effective prediction of future viral zoonoses requires an in-depth understanding of the heterologous viral population in key animal species that will likely serve as reservoir hosts or intermediates during the next viral epidemic. The importance of bats as natural hosts for several important viral zoonoses, including Ebola, Marburg, Nipah, Hendra, and rabies viruses and severe acute respiratory syndrome-coronavirus (SARS-CoV), has been established; however, the large viral population diversity (virome) of bats has been partially determined for only a few of the similar to 1,200 bat species.

5 kg required tracheostomy Median duration from surgery to trach

5 kg required tracheostomy. Median duration from surgery to tracheostomy was 36 days (range 10-145 days). Genetic syndromes or major noncardiac comorbidities were present in 40% of patients. Biventricular repair was performed in 34 patients and univentricular

repair in 25. Tetralogy of Fallot variants (29%) and coarctation +/- ventricular septal defect (21%) PXD101 constituted the majority of biventricular lesions associated with tracheostomy, whereas unbalanced atrioventricular septal defect and hypoplastic left heart syndrome with highly restrictive atrial septal defect accounted for 52% of the single ventricle group. Indications for tracheostomy included the following: multifactorial (37%), tracheobronchomalacia, (24%), cardiac (12%), bilateral vocal cord paralysis (10%), bilateral diaphragm paralysis (2%), and other airway issues (15%). Hospital survival was 75% with intermediate-term (median, 25.5

months; range, 1-122 months) survival of 53%. Of 25 single ventricle patients, 6 (24%) had successful completion of the Fontan procedure. Of 12 patients with single ventricle who were ventilator-dependent after initial repair, 10 Sotrastaurin clinical trial died, 1 remains at hemi-Fontan, and 1 has undergone completion of the Fontan procedure.

Conclusions: Requirement for tracheostomy in pediatric patients after cardiac surgery was associated with significant mortality. Patients with single ventricle have the highest late death rate and those with chronic ventilator dependency were unlikely to undergo successful Fontan completion. (J Thorac Cardiovasc Surg 2011;141:413-8)”
“Punctate white matter lesions (PWML) are recognized with magnetic

resonance imaging (MRI) as hypersignal on T1-weighted imaging and hyposignal on T2-weighted imaging. Our aim was to assess how often a hemorrhagic see more component was present in PWML using susceptibility-weighted imaging (SWI).

Seventeen preterm (gestational age, 25-34 weeks) and seven full-term infants (age at MRI, 37-42 weeks) with PWML were included. Seven preterm infants had sequential MRIs. PWML were diagnosed with conventional MRI and compared with SWI, where signal loss is suggestive of hemorrhage. The pattern of associated brain lesions was taken into account, and the percentage of lesions with signal loss on SWI was calculated for each infant.

A significantly higher percentage of signal loss on SWI (median, 93.9%) was found among infants with germinal matrix and intraventricular hemorrhage as the primary diagnosis (n = 8) compared to those with a primary diagnosis of white matter injury (n = 14; median, 14.2%; p < 0.01). In the infants with serial MRIs, a reduction in the number of PWML and/or signal loss on SWI was noted at term equivalent age. In the patient who died, cystic lesions, associated with hemorrhage and gliosis, were demonstrated on histology.

SWI can distinguish hemorrhagic and non-hemorrhagic PWML. Signal loss on SWI was more common when PWML were associated with an intraventricular hemorrhage.

The majority of participants rated their own driving as good to e

The majority of participants rated their own driving as good to excellent. Of the 47 (17%) drivers who were rated as potentially unsafe to drive, 66% rated their own driving as good to excellent. Drivers who made critical errors, where the driving instructor had to take control of the vehicle, had no lower self-rating of driving ability than the rest of the group. The discrepancy in self-perceptions of driving ability and participants’ safety rating on the on-road assessment was significantly associated with self-reported retrospective crash rates, where those drivers who displayed greater overconfidence in

their own driving were significantly more likely to report a crash.

Conclusions. This study demonstrates that older drivers with the greatest mismatch between Acadesine research buy actual and self-rated driving ability pose the greatest risk to road safety. Therefore, licensing authorities should not assume that when older individuals’ driving abilities begin to decline they Caspase Inhibitor VI clinical trial will necessarily be aware of these changes and adopt appropriate compensatory driving behaviors; rather, it is essential that evidence-based assessments are adopted.”
“beta-lactoglobulin (LG) contains nine beta-strands (strands A-I) and one a-helix. Strands A-H form a beta-barrel. At neutral pH, equine LG (ELG) is monomeric, whereas bovine LG (BLG) is dimeric, and the I-strands

of its two subunits form an intermolecular beta-sheet. We previously constructed a chimeric ELG in which the sequence of the I-strand was replaced with that of BLG. This chimera did not dimerize. For this study, we constructed the new chimera we call Gyuba (which means cow and horse in Japanese). The amino acid sequence of Gyuba includes the sequences of the BLG secondary structures and those of the ELG loops. The crystal structure of Gyuba is very similar to that of BLG and indicates that Gyuba dimerizes via the intermolecular beta-sheet formed by the two I-strands. Thus, the entire arrangement

of the secondary structural elements is important for LG dimer formation.”
“Combining the concepts of synthetic symmetrization with the approach of engineering metal-binding sites, we have developed a new crystallization ADP ribosylation factor methodology termed metal-mediated synthetic symmetrization. In this method, pairs of histidine or cysteine mutations are introduced on the surface of target proteins, generating crystal lattice contacts or oligomeric assemblies upon coordination with metal. Metal-mediated synthetic symmetrization greatly expands the packing and oligomeric assembly possibilities of target proteins, thereby increasing the chances of growing diffraction-quality crystals. To demonstrate this method, we designed various T4 lysozyme (T4L) and maltose-binding protein (MBP) mutants and cocrystallized them with one of three metal ions: copper (Cu2+), nickel (Ni2+), or zinc (Zn2+).