Genetic evidence of a strong functional constraint of neurotrypsin during primate evolution

Neurotrypsin is one of the extra-cellular serine proteases that are predominantly expressed in the brain and involved in neuronal development and function. Mutations in humans are associated with autosomal recessive non-syndromic mental retardation (MR). We studied the molecular evolution of neurotrypsin by sequencing the coding region of neurotrypsin in 11 representative non-human primate species covering great apes, lesser apes, Old World monkeys and New World monkeys. Our results demonstrated a strong functional constraint of neurotrypsin that was caused by strong purifying selection during primate evolution, an implication of an essential functional role of neurotrypsin in primate cognition. Further analysis indicated that the purifying selection was in fact acting on the SRCR domains of neurotrypsin, which mediate the binding activity of neurotrypsin to cell surface or extracellular proteins. In addition, by comparing primates with three other mammalian orders, we demonstrated that the absence of the first copy of the SRCR domain (exon 2 and 3) in mouse and rat was due to the deletion of this segment in the murine lineage. Copyright (C) 2005 S. Karger AG, Basel.

Rapid evolution, genetic variations, and functional association of the human spermatogenesis-related gene NYD-SP12

NYD-SP12 is a recently identified spermatogenesis-related gene with a pivotal role in human testis development. In this study, we analyzed between-species divergence and within-species variation of NYD-SP12 in seven representative primate species, four wo

CpG islands or CpG clusters: how to identify functional GC-rich regions in a genome?

Background: CpG islands (CGIs), clusters of CpG dinucleotides in GC-rich regions, are often located in the 5' end of genes and considered gene markers. Hackenberg et al. ( 2006) recently developed a new algorithm, CpGcluster, which uses a completely diffe

Functional characterization of the human-specific (type II) form of kallikrein 8, a gene involved in learning and memory

Kallikrein 8 (KLK8) is a serine protease functioning in the central nervous system, and essential in many aspects of neuronal activities. Sequence comparison and gene expression analysis among diverse primate species identified a human-specific splice for

Functional consequences of new exon acquisition in mammalian chromodomain Y-like (CDYL) genes

The origin of new exons is an important mechanism for proteome diversity. Here, we report the recurrent origination of new exons in mammalian chromodomain Y-like (CDYL) genes and the functional consequences associated with the acquisition of the new exons

Maturation of rhesus monkey oocytes in chemically defined culture media and their functional assessment by IVF and embryo development

This study compared success of in-vitro maturation of rhesus monkey oocytes in protein-free versus serum-containing culture systems, assessed by embryo development subsequent to IVF. Four media were tested: (i) modified Connaught Medical Research Laborato

Cryopreservation of rhesus macaque (Macaca mulatta) spermatozoa and their functional assessment by in vitro fertilization

Although spermatozoa from several species of nonhuman primates have been cryopreserved, there has been no report of success with rhesus macaque spermatozoa as judged by functional assays. Two Tris-egg yolk freezing media. TEST and TTE. which have: been successfully used for cynomolgus macaque (Macaca fascicularis) spermatozoa, were compared for cryopreservation of spermatozoa From four rhesus macaques (Macaca mulatta). The postthaw motility (percentage and duration) of spermatozoa cryopreserved in TTE was much higher than that for spermatozoa cryopreserved in TEST. The function of sperm cryopreserved in TTE was evaluated by in vitro fertilization or oocytes collected from gonadotropin-stimulated prepubertal rhesus macaques. Of the inseminated oocytes. 82 +/- 13% were fertilized and 63 +/- 22 and 39 +/- 21% of the resulting zygotes developed into morulae and blastocysts. respectively. These results indicate that rhesus macaque spermatozoa can be effectively cryopreserved in TTE medium. This finding will facilitate the application of in vivo and in vitro assisted reproductive technologies in this species. (C) 2001 Academic Press.

Molecular and functional characterization of a c-type lysozyme from the Asian corn borer, Ostrinia furnacalis

Some lepidopteran lysozymes have been reported to display activity against Gram-positive and Gram-negative bacteria, in contrast to most lysozymes that are active only against Gram-positive bacteria. OstrinLysC, a c-type lysozyme, was purified from the As

Duplication and functional diversification of pancreatic ribonuclease (RNASE1) gene

Adaptation is one of the most fundamental issues in the studies of organismal evolution. Pancreatic ribonuclease is a very important digestive enzyme and secreted by the pancreas. Numerous studies have suggested that RNASE1 gene duplication is closely related to the functional adaptation of the digestive system in the intestinal fermentation herbivores. RNASE1 gene thus becomes one of the most important candidate genetic markers to study the molecular mechanism of adaptation of organisms to the feeding habit. Interestingly, RNASE1 gene duplication has also been found in some non-intestinal fermentation mammals, suggesting that RNASE1 gene may have produced novel tissue specificity or functions in these species. In this review, RNASE1 gene and its implications in adaptive evolution, especially in association with the feeding habit of organisms, are summarized.

主分量分析(PCA)在动物分类学中的运用

就主量分析(PCA)的基本原理、 运用发展过程及在动物分类学上的应用作了 阐明。并以亚洲疣猴类5个属为例, 利用其面颅和颅骨的6项变量进行分析, 且 叙述了PCA的主要计算过程。 结果表明, 在分类过程中, 主要是面颅的凸度和宽 度结构起贡献作用。图5参21

Structural and functional characterization of the human CCR5 receptor in complex with HIV gp120 envelope glycoprotein and CD4 receptor by molecular modeling studies

The entry of human immunodeficiency virus (HIV) into cells depends on a sequential interaction of the gp120 envelope glycoprotein with the cellular receptors CD4 and members of the chemokine receptor family. The CC chemokine receptor CCR5 is such a receptor for several chemokines and a major coreceptor for the entry of R5 HIV type-1 (HIV-1) into cells. Although many studies focus on the interaction of CCR5 with HIV-1, the corresponding interaction sites in CCR5 and gp120 have not been matched. Here we used an approach combining protein structure modeling, docking and molecular dynamics simulation to build a series of structural models of the CCR5 in complexes with gp120 and CD4. Interactions such as hydrogen bonds, salt bridges and van der Waals contacts between CCR5 and gp120 were investigated. Three snapshots of CCR5-gp120-CD4 models revealed that the initial interactions of CCR5 with gp120 are involved in the negatively charged N-terminus (Nt) region of CCR5 and positively charged bridging sheet region of gp120. Further interactions occurred between extracellular loop2 (ECL2) of CCR5 and the base of V3 loop regions of gp120. These interactions may induce the conformational changes in gp120 and lead to the final entry of HIV into the cell. These results not only strongly support the two-step gp120-CCR5 binding mechanism, but also rationalize extensive biological data about the role of CCR5 in HIV-1 gp120 binding and entry, and may guide efforts to design novel inhibitors.

对-氯代苯胺(PCA)在填充床生物反应器中的降解作用

以氯代苯胺（ＰＣＡ）为选择基质，用驯化技术从降解对二氯苯（ｐＤＣＢ）的富集培养物中得到了以同化ＰＣＡ为唯一碳源和氮源的混合微生物．将这种固定在填充床反应器中的微生物用于ＰＣＡ的降解作用研究中．在该反应器里，ＰＣＡ的生物降解遵循Ｌｏｇｉｓｔｉｃ方程ｑ＝ｑｍａｘ／（１＋ｅα－βＵｖ）．由方程求出了主要的动力学常数，Ｋｓ（半速率常数）和ｑｍａｘ（最大比基质降解速率）．于ＰＣＡ降解的同时，释放氯离子到培养基中．在水力停留时间３ｈ，进水ＰＣＡ浓度为３６０ｍｇ·Ｌ－１情况下，基质的体积降解率达到１２５ｍｇ·Ｌ－１