The role of histones and their modifications in the informative content of chromatin

It is traditionally accepted that the DNA sequence cannot by itself explain all the mechanisms necessary for the development of living beings, especially in eukaryotes. Indeed part of the information used in these processes is stored in other ways, generally called epigenetic, whose molecular mechanisms are mostly unknown. The ultimate explanation for them might reside in the non-DNA moiety of chromatin which may play an active role in heredity (chromatin information). Histones are the universal structural component of chromatin. However, recent studies strongly suggest that histones, and their modifications — especially the reversible acetylation of lysines — may act as a recognition signal for regulatory proteins and they may participate, for this reason, in gene regulation. This type of information could be maintained through its replication and, ultimately, it could form the molecular basis of certain processes related to the development of the eukaryotic organisms.     

"青藏高原形成演化及其环境资源效应"研究进展

青藏高原是我国地学、生物学、资源与环境科学有特色的优势研究领域和难得的天然实验室.青藏高原研究对解决岩石圈地球动力学和全球环境变化有重要意义,对高原区域可持续发展也有广阔的应用前景.本项目选择青藏高原的典型地区为重点,特别注意从高原与毗邻地区的联系,以至从全球尺度探讨高原的各种过程,目标集中在大陆碰撞过程和高原隆升过程,以过程为主线贯通碰撞机制、环境变化和资源分布规律的研究;时间上着重新生代以来,在不同精细时间尺度上定量地描述碰撞和隆升的动态过程及环境变化.主要研究内容包括以下4个方面大陆岩石圈碰撞过程及其成矿效应;高原隆升过程与东亚气候环境变化;青藏高原现代表生过程及相互作用机理;青藏高原区域系统相互作用的综合研究.项目的实施紧密围绕预期目标,深入分析,加强学科交叉和综合研究,取得了如下主要研究进展和创新成果印度大陆与欧亚大陆初始碰撞时限;青藏高原南北缘山盆岩石圈尺度的构造关系;新生代高原北部重大的构造变形隆升事件序列;高分辨率气候动态过程及变化趋势;高原隆升对亚洲季风发展变化的影响;高原不同生态系统类型温室气体吸收与排放.同时,本文也论述了项目的实施在青藏高原研究的科学前沿及区域发展的国家需求等方面产生的影响和作用,并展望了青藏高原研究重要的前沿领域.     

膳食硫代葡萄糖苷衍生物抗癌活性及预防癌症的研究进展

膳食硫代葡萄糖苷广泛存在于十字花科蔬菜,如西兰花、卷心菜、球芽甘蓝和花椰菜等,其衍生物萝卜硫素(SFN)、苯乙基异硫氰酸酯(PEITC)等,在细胞中靶向酶与受体,通过调控细胞信号通路与表观遗传变异,上调II相解毒酶/抗氧化酶,降低炎症介质,诱导抑制肿瘤、促凋亡、抗氧化和抗炎基因等表达,逆转、抑制癌症形成;从分子靶向探讨硫代葡萄糖苷衍生物SFN、PEITC的抗癌活性,概述近年来SFN、PEITC预防癌症的最新研究进展,提醒人们从膳食角度增强对癌症等疾病的防范意识。     

Chromatin structure contribution to the synaptonemal complex formation

Meiosis is a key cellular and molecular process for sexual reproduction contributing to the genetic variability of organisms. This process takes place after DNA replication and consists in a double cellular division, giving rise to four haploid daughter cells or gametes. Meiotic recombination between homologous chromosomes, in the meiotic prophase I, is mediated by a tripartite structure named Synaptonemal Complex (SC). The SC is a peptidic scaffold in which the chromatin of homologous chromosomes is organized during the pachytene stage, holding chromosomes together until the meiotic recombination and genetic exchange have taken place. The role of chromatin structure in formation of the SC and the meiotic recombination at meiotic prophase I remain largely unknown. In this review we address the epigenome contribution to the SC formation at meiotic prophase I, with particular attention on the chromatin structure modifications occurring during the sub-stages of meiotic prophase I. Received 18 September 2008; received after revision 10 October 2008; accepted 24 October 2008     

颅面生长的控制理论

颅面生长的控制理论是颅面生长发育理论的重要组成部分。本文综述了颅面生长的遗传控制理论，功能基质假说和伺服系统理论等的基本内容，介绍了各种理论的特点和局限性，阐述了颅内生长控制理论从遗传到渐成影响的认识变化，并应用各种理论解释了颅面正常生长发育深入研究遗传的渐成因素对因素对颅面生长控制的作用。     

深切河谷岩体结构的表生改造

岩体结构的表生改造是指河谷下切过程中 ,由于应力释放 ,岸坡岩体将向临空面方向发生卸荷回弹变形 ,谷坡应力场产生新的调整 ,伴随这一过程岩体结构所产生的一系列新的变异或变化。岩体结构的表生改造一般具有两类形式 ,即原有构造或原生结构面的进一步改造 ,或新的表生破裂体系的形成。其结果是在河谷岸坡一定深度范围内 ,形成类似于地下硐室围岩“松动圈”的岸坡卸荷带 ,从而恶化岩体的工程性状 ,降低结构面强度 ,对工程具有明显的影响和作用。该文采用有限元法模拟了某水电站坝区岩体结构的表生改造 ,探讨了地应力在表生改造中的作用 ,分析了表生改造对岩体结构的控制作用 ,为深入研究坝区岩体结构奠定了基础     

表观遗传试剂诱导滇重楼内生真菌 Hypomyces sp.CLG4次生代谢产物的研究

采用高效液相色谱(HPLC)分析添加HDACI,500μM恩提诺特的H.sp.CLG4.培养萃取物与对照的差异,硅胶柱层析、反相柱层析、半制备高效液相等色谱方法对添加表观遗传试剂的Hypomyces sp.CLG4.次级代谢产物进行分离纯化,并利用现代波谱分析方法对化合物进行结构鉴定.研究组蛋白去乙酰化酶抑制剂(his...