中间纤维蛋白的同源性分析研究

利用计算机对３１种中间纤维蛋白 同源性进行了分析，结果发现了３个保守序列，这些序列可用于研究中间纤维的起源，进化与克隆物中间纤维基因。     

The cytosolic and membrane components required for peroxisomal protein import

Peroxisomes are vital intracellular organelles which house enzymes involved in a variety of metabolic pathways. The large number of human disorders associated with flawed peroxisome biogenesis emphasizes the importance of protein targeting to, and translocation across, the peroxisomal membrane. This brief review will summarize some of the emerging themes of peroxisomal protein import, specifically addressing the targeting signals possessed by constituent proteins, as well as the cytosolic, membrane and luminal components of the import machinery. Although a detailed understanding of the molecular mechanisms of peroxisomal protein import is not yet available, remarkable progress has been made in the field in recent years. An overview of these advances will be presented.     

Studies onHolothuria polii (Echinodermata) antibacterial proteins. I. Evidence for and activity of a coelomocyte lysozyme

Summary Lysozyme activity has been detected in coelomocyte lysate of the echinodermHolothuria polii. The bacteriolytic reaction was stable when the lysate was heated in acidic buffer but heat-labile in alkaline medium. An incubation temperature of 35°C, acidic pH values (5.2 and 6.2) and an ionic strength of 0.175 were found to be the best conditions for the coelomocyte enzymatic activity. A low level of lysozyme was also evidenced in cell-free coelomic fluid where it could represent a basal defense level of bacteriolytic molecules released by the coelomocytes.Acknowledgments. This work was supported in part by a grant from MRES (C. C.). The authors thank M. Lasségues and F. Lassalles for their help and criticism.     

Effects of antisense CENP-Bon the proliferation of HeLa (Tet-off) cells

In order to study the change of the expression of centromere protein B (CENP-B) caused by anfisense tcansfection, proto-eukaryotically expressed fused protein GST-CENP-B (65 ku) was injected into mouse, and a peculiar anti-CENP-B serum MaCenpB was collected. A strain of transfected HeLa Tet-off cell HaCb, which contains antisense CENP-B expressing vector pBI-EGFP-as-CenpB, was prepared. Northern blot and Western blot were used to analyze the repression of internal CENP-B in transfected cells. According to the growth curve, the proliferation of HeLa (Tet-off) is repressed by antisense CENP-B, and the multiplication time is prolonged for 32.81 h. The analysis of flow cytometry revealed that, compared with HeLa (Tet-off), the G1 cell population of HaCb is increased (△G1 = 9%) while S fraction is decreased (△S = 11%), but the G2/M phase is nearly unchanged (△G2/M=3%). In the meanwhile, the mitotic index of HaCb declines greatly compared with that of HeLa (Tet-off). Immunofluorescence showed that the assembling of centromeres in HaCb cell is arrested. These results suggest that a normal expression of CENP-B may be necessary for cell proliferation.     

植物GRAS蛋白的结构与功能

GRAS蛋白是近年来研究较多的一大类植物体中特有的蛋白家族，目前仅在拟南芥中即分离出38种蛋白质，其中不少蛋白的结构与功能已得了清晰的认识，它们的功能函盖了从分生组织的生长到激素与光的信号转导的调控的广大范围，本文对植物GRAS蛋白的结构与功能进行综述．     

Testosterone secretion by Mongolian gerbil interstitial cells during short-term incubation depends on androgen precursors and serum proteins but not on gonadotrophins

Summary Interstitial cells from the testes of the Mongolian gerbil have been used to investigate the effects of serum proteins on testosterone production stimulated by hCG and steroidal precursors. Short-term incubation of interstitial cells with progesterone or DHEA resulted in a rapid increase of testosterone secretion; this effect was even more pronounced in the presence of calf serum. On the other hand, addition of hCG (10 mIU) had no significant effect on testosterone release during the 30-min incubation. These results demonstrate that the magnitude of the steroidogenic response of short-term incubated interstitial cells is a complex function, mainly of precursor concentrations and binding capacities of serum proteins but not of gonadotrophins.8 October 1986     

Intracellular sterol trafficking

Summary Sterols are acquired by cells either biosynthetically by the interaction of cytoplasmic and endoplasmic reticulum elements, or by endocytosis. The subcellular distribution of sterols, however, argues that sterols are trafficked quickly from sites of acquisition to target membranes, particularly the plasma membrane. The mechanisms mediating this movement might include aqueous diffusion, vesicles of either a unique pathway or of the protein secretory pathway, or carrier proteins. These mechanisms are discussed and the limited data concerning each are presented. Finally, a theory is proposed which describes how sterols and other membrane reinforcing molecules might have driven the evolution of intracellular membranes, thus establishing the dynamic membrane system of modern eukaryotes.     

食用菜籽蛋白的提取及其功能特性的研究

研究了食用菜籽蛋白的提取方法及其功能特性，并对其应用前景进行了讨论。