Aims/hypothesis. The Human Genome Project seeks to identify all genes with the ultimate goal of evaluation of relative expression levels in physiology and in disease states. The purpose of the current study was the identification of the most abundant transcripts in human pancreatic islets and their relative expression levels using Serial Analysis of Gene Expression. Methods. By cutting cDNAs into small uniform fragments (tags) and concatemerizing them into larger clones, the identity and relative abundance of genes can be estimated for a cDNA library. Approximately 49 000 SAGE tags were obtained from three human libraries: (i) ficoll gradient-purified islets (ii) islets further individually isolated by hand-picking, and (iii) pancreatic exocrine tissue. Results. The relative abundance of each of the genes identified was approximated by the frequency of the tags. Gene ontology functions showed that all three libraries contained transcripts mostly encoding secreted factors. Comparison of the two islet libraries showed various degrees of contamination from the surrounding exocrine tissue (11 vs 25%). After removal of exocrine transcripts, the relative abundance of 2180 islet transcripts was determined. In addition to the most common genes (e.g. insulin, transthyretin, glucagon), a number of other abundant genes with ill-defined functions such as proSAAS or secretagogin, were also observed. Conclusion/interpretation. This information could serve as a resource for gene discovery, for comparison of transcript abundance between tissues, and for monitoring gene expression in the study of beta-cell dysfunction of diabetes. Since the chromosomal location of the identified genes is known, this SAGE expression data can be used in setting priorities for candidate genes that map to linkage peaks in families affected with diabetes. [Diabetologia (2004) 47:284-299]

Medium-chain acyl-CoA dehydrogenase (MCAD) is a highly regulated mitochondrial flavo-enzyme that catalyzes the initial reaction in fatty acid beta-oxidation. Deficiency of MCAD is a common inherited defect in energy metabolism. We have previously shown that the mRNA encoding MCAD in an MCAD-deficient child is homozygous for the point mutation A985 to G [Kelly et al. (1990) Proc. Natl. Acad. Sci. U.S.A. 87, 9236-9420]. To define the molecular basis of MCAD deficiency and as an initial step in the study of the regulation of MCAD gene expression, we determined the structure and organization of the human MCAD gene. The gene is comprised of 12 exons which span 44 kb of DNA. Comparison of the MCAD gene to MCAD mRNAs from the MCAD-deficient child revealed that missplicing was common, resulting in a variety of exon deletions and intron insertions. The MCAD gene promoter region is extremely GC-rich and lacks prototypical TATA and CAAT boxes. Several regions upstream of the promoter are homologous with mitochondrial enhancers purportedly involved in coordinate expression of nuclear genes encoding mitochondrial proteins. Transfection of chimeric plasmid constructs with 299 bp of upstream sequence into HepG2 cells revealed high-level transcriptional activity. We conclude that the precursor MCAD mRNA is misspliced to a high degree and complexity in association with the G985 mutation and the MCAD gene contains a strong promoter which shares some structural features with other "housekeeping" genes encoding mitochondrial proteins.

Gender as a critical, intrinsic, non-immunologic factor plays a pivotal role in the field of transplantation. The gender of donors and recipients is involved in the entire process, including organ donation and transplant surgery. This review article aims to summarize the literature related to the role of gender in solid organ donation and transplantation and to unveil the underlying mechanism by which gender mismatch between donor and recipient impacts transplant rejection. A systematic search was conducted through PubMed by using the following key words: "gender", or "sex", and "transplant", "organ donation" for published articles. The prima facie evidence demonstrated that females are more likely to donate their organs and are less willing than males to accept transplant surgery; however, their donated liver organs will have a higher risk of graft failure compared with males. With respect to kidney, heart, and lung transplantations, the role of gender remains controversial. Results of animal studies support the negative impact of gender mismatch on allograft function. In conclusion, our present study advances the knowledge of gender issues in the field of solid organ donation and transplantation. In general, gender mismatch is not advantageous to transplant outcome, as evidenced by many aspects of biological investigations on immunogenicity of H-Y antigen to females. Therefore, gender issues should be highlighted and an a priori intervention is needed to improve graft survival in clinical practice.

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Background:The presence of no-reflow can increase the risk of major adverse cardiac events and is widely regarded as an important sign of serious prognosis. Previous studies show that laminin receptor (LR) is closely related to the morphology and function of microvessels. However, whether LR is involved in the occurrence and development of no-reflow is still unknown. Methods: In vivo, positron emission tomography (PET) perfusion imaging was performed to detect the effects of intramyocardial gene (LR-AAV and LR-siRNA-AAV) delivery treatment on the degree of no-reflow. In vitro, LC-MS/MS analysis was conducted to identify the LR phosphorylation sites of human cardiac microvascular endothelial cells (HCMECs) treated with oxygen-glucose deprivation (OGD) for 4 h. Western blot analyses were used to evaluate the phosphorylation levels of LR at residues Tyr47 (phospho-Tyr47-LR/pY47-LR) and Thr125 (phospho-Thr125-LR/pT125-LR) and their effects on the phosphorylation of VE-cadherin residue Ser665 (phospho-Ser665-VE-cad). Findings: LR over-expression, LR T125A (phosphonull) and LR Y47A (phosphonull) treatments were found to reduce the level of phospho-Ser665-VE-cad, and subsequently maintain adherent junctions and endothelial barrier integrity in hypoxic environments. Mechanistically, TIMAP/PP1c can combine with LR on the cell membrane to form a novel LR-TIMAP/PP1c complex. The level of pY47-LR determined the stability of LR-TIMAP/PP1c complex. The binding of TIMAP/PP1c on LR activated the protein phosphatase activity of PP1c and regulated the level of pT125-LR. Interpretation: This study demonstrates that low level of phospho-LR reduces no-reflow area through stabilizing the LR-TIMAP/PP1c complex and promoting the stability of adherens junctions, and may help identify new therapeutic targets for the treatment of no-reflow.