Identification of laccase gene family members in peach and its relationship with chilling induced browning / 生物工程学报

The laccase (PpLAC) gene family members in peach fruit were identified and the relationship between their expression pattern and chilling induced browning were investigated. The study was performed using two varieties of peaches with different chilling tolerance, treated with or without exogenous γ-aminobutyric acid (GABA) during cold storage. Twenty-six genes were screened from the peach fruit genome. These genes were distributed on 6 chromosomes and each contained 5-7 exons. The PpLAC gene family members shared relatively similar gene structure and conserved motifs, and they were classified into 7 subgroups based on the cluster analysis. Transcriptome sequencing revealed that the expression levels of PpLAC7 and PpLAC9 exhibited an increasing pattern under low temperature storage, and displayed a similar trend with the browning index of peach fruit. Notably, GABA treatment reduced the degree of browning and inhibited the expression of PpLAC7 and PpLAC9. These results suggested that PpLAC7 and PpLAC9 might be involved in the browning of peach fruit during cold storage.

Gene polymorphism of insulin receptor substrate-1 in Northern Chinese Han pedigrees with type 2 diabetes mellitus / 中国病理生理杂志

AIM: To investigate the role of gene poly mo rphisms of insulin receptor substrate-1 (IRS-1) in northern Chinese Han pedigree s with type 2 diabetes mellitus (DM). METHODS: Polymorphisms in codon 804 and 971 of IRS-1 gene in 80 unrelated patients with type 2 DM and 80 control subjects were analyzed by polym erase chain reaction-sequence specific primer(PCR-SSP) technique followed by pol yacrylamide gel electrophoresis and silver staining. RESULTS: The frequencies (GCA→GCG) in codon 804 of IRS-1 gene w ere significantly higher in type 2 DM than normal subjects(0.200 vs 0.062, P