基因及其顺式调控元件在动物表型进化中的作用

顺式调控假说是当前进化发育生物学中重要的理论之一, 该假说认为顺式调控元件的进化是调控外表性状进化的主要遗传机制。然而越来越多的实验结果表明, 仅靠顺式调控假说远不足以解释复杂的进化发育过程, 其他因素也会导致表型的进化, 如：与顺式调控元件相联基因的蛋白序列改变; 基因及染色体组复制; 蛋白结构域与顺式调控元件的灵活性等。文章回顾了近年来顺式调控元件以及与顺式调控元件相联基因的进化发育研究, 探讨了进化发育生物学研究的新方法与新思路。     

果蝇中顺式调控序列的进化

顺式调控序列(cis-regularory sequences)是与基因表达调控相关、能够被调控因子特异性识别和结合的非编码DNA序列。顺式调控序列可以通过增减所含转录因子结合位点的数目,重构转录调控网络,以精准调控基因的时空表达模式,从而调控动物的生理和形态表型。顺式调控假说认为顺式调控序列进化是自然界丰富的动物表型进化的主要遗传机制。本文首先简述了顺式调控序列的结构和功能,然后重点讨论了近年来顺式调控序列进化调控果蝇表型进化如刚毛表型进化、色素沉积表型进化和胚胎发育方面的研究进展,阐释了顺式调控序列进化是动物表型进化的主要遗传机制之一。最后本文展望了顺式调控序列未来研究方向,例如应用功能基因组研究、开展ENCODE计划等,为进化发育生物学中顺式调控序列的研究提供了参考。     

利用进化比较的方法确定β珠蛋白基因簇调控的顺式元件

利用进化比较的方法对我、兔子和灵长类Ｇａｌａｇｏ的β珠蛋白基因以及所在的β珠蛋白基因簇进行分析,确定了可能的基因调控的顺式元件,并与一些实验结果进行比较,发现利用进行比较的方法确定基因调控的顺式元件是一种简单可行的方法。     

真核生物转录调控进化的研究进展

转录调控进化在真核生物的表型进化中发挥了重要作用.首先介绍了基因转录调控元件,包括基因上游调控序列和转录因子的进化特点,然后阐述了转录调控进化在生物体进化中所起的作用,最后提出了当前研究转录调控进化所面临的问题和挑战.     

进化发育生物学--发育、进化和遗传的再联合

发育生物学和进化生物学,以及遗传学历史上曾一度是彼此不分的统一体,后来由于各自研究重点的不同和相应研究手段的独立发展彼此分道扬镳了。如今,由于分子遗传学研究手段的革新使得基因序列测定成为分析发育机理、区分物种和评估种间亲缘关系的常规手段,三者又在基因水平上再度统一起来了,并形成一门被称为进化发育生物学（ｅｖｏｌｕｔｉｏｎａｒｙ ｄｅｖｅｌｏｐｍｅｎｔａｌ ｂｉｏｌｏｇｙ）的新学科。     

工业微生物遗传和环境扰动的调控和适应进化

开发工业微生物,使其利用可再生的原料生产生物燃料、大宗化学品、食品添加剂和营养品、药物以及工业酶等,是发展生物产业的基础。工业微生物高产和胁迫抗性等鲁棒性状受复杂遗传调控网络控制,其改造需要从全基因组尺度进行系统的全局的多位点的扰动,以达到快速积累多样性基因型突变并产生所期望的表型。文中对工业微生物鲁棒性状的遗传调控与胁迫响应机制、基因组全局扰动与多位点快速进化以及细胞水平氧还平衡的全局扰动进行了简要综述,未来需要继续借助系统生物学和合成生物学手段,进一步加强对工业环境下工业微生物鲁棒性状调控机理的解析与建模预测以及系统的工程改造。     

昆虫性信息素生物合成系统脱饱和酶与进化基因组学

多基因家族在进化过程中曾经历了不同程度的基因复制和缺失,并由此导致一些基因在漫长的进化年代中得以存在和表达,而另一些只是在特定时期内短暂出现,之后或者逐渐消失或者沉默进而失去其生物学功能,同时新的基因在复制过程中不断产生。这一现象被称作“产生与死亡演化”(birth-and-death evolution),对于产生新的遗传系统和复杂表型特征具有重要作用。昆虫性信息素生物合成系统脱饱和酶多基因家族的进化过程就是这方面一个典型的例证。     

分子·形态·进化

分子·形态·进化马德如（南开大学分子生物学研究所,天津３０００７１）关键词异位同形盒,发育,进化最早重视‘异位同形’（ｈｏｍｅｏｓｉｓ）这类发育变异并首创此词的是Ｗ．Ｂａｔｅｓｏｎ。在他１８９４年出版的《关于变异的研究资料》一书中列举的例子有：昆虫生...     

"遗传与进化"模块的解读

“遗传与进化”是高中生物学课程内容的共同必修模块之一,内容包括：遗传的细胞基础、遗传的分子基础、遗传的基本规律、生物的变异、人类遗传病、生物的进化6部分。     

Repeated modification of early limb morphogenesis programmes underlies the convergence of relative limb length in Anolis lizards

The independent evolution of similar morphologies has long been a subject of considerable interest to biologists. Does phenotypic convergence reflect the primacy of natural selection, or does development set the course of evolution by channelling variation in certain directions? Here, we examine the ontogenetic origins of relative limb length variation among Anolis lizard habitat specialists to address whether convergent phenotypes have arisen through convergent developmental trajectories. Despite the numerous developmental processes that could potentially contribute to variation in adult limb length, our analyses reveal that, in Anolis lizards, such variation is repeatedly the result of changes occurring very early in development, prior to formation of the cartilaginous long bone anlagen.     

The interaction of sexually and naturally selected traits in the adaptive radiations of cichlid fishes

The question of how genetic variation translates into organismal diversity has puzzled biologists for decades. Despite recent advances in evolutionary and developmental genetics, the mechanisms that underlie adaptation, diversification and evolutionary innovation remain largely unknown. The exceptionally diverse species flocks of cichlid fishes are textbook examples of adaptive radiation and explosive speciation and emerge as powerful model systems to study the genetic basis of animal diversification. East Africa's hundreds of endemic cichlid species are akin to a natural mutagenesis screen and differ greatly not only in ecologically relevant (hence naturally selected) characters such as mouth morphology and body shape, but also in sexually selected traits such as coloration. One of the most fascinating aspects of cichlid evolution is the frequent occurrence of evolutionary parallelisms, which has led to the question whether selection alone is sufficient to produce these parallel morphologies, or whether a developmental or genetic bias has influenced the direction of diversification. Here, I review fitness-relevant traits that could be responsible for the cichlids' evolutionary success and assess whether these were shaped by sexual or natural selection. I then focus on the interaction and the relative importance of sexual vs. natural selection in cichlid evolution. Finally, I discuss what is currently known about the genes underlying the morphogenesis of adaptively relevant traits and highlight the importance of the forthcoming cichlid genomes in the quest of the genetic basis of diversification in this group.     

水稻生长发育多效基因DDF1的遗传分析与基因定位

植物中存在许多多效性基因,它们在调控植物的营养生长与生殖发育过程中起着关键性作用。文章在籼稻育种材料中发现了一个植株显著矮化且花器官明显变异的突变体ddf1(dwarf and deformed flower 1)。遗传分析表明,该突变体由单基因隐性突变所致,这说明该基因是一个同时控制营养生长和生殖发育的多效性基因,暂命名为DDF1。为了定位该基因,将ddf1杂合体与热带粳稻品种DZ60杂交,建立了F2定位群体,利用水稻RM系列微卫星标记,通过混合分离分析(BSA)和小群体连锁分析,将DDF1初步定位在水稻第6号染色体RM588和RM587标记之间,与两标记的遗传距离分别为3.8 cM和2.4 cM。进一步利用已经公布的水稻基因组序列,在初步定位的区间内开发新的SSR标记,将DDF1定位在165 kb的区间内。该结果为克隆DDF1奠定了基础。     

The evolution of eusociality in allodapine bees: workers began by waiting

Understanding how sterile worker castes in social insects first evolved is one of the supreme puzzles in social evolution. Here, we show that in the bee tribe Allodapini, the earliest societies did not entail a foraging worker caste, but instead comprised females sharing a nest with supersedure of dominance. Subordinates delayed foraging until they became reproductively active, whereupon they provided food for their own brood as well as for those of previously dominant females. The earliest allodapine societies are, therefore, not consistent with an 'evo-devo' paradigm, where decoupling of foraging and reproductive tasks is proposed as a key early step in social evolution. Important features of these ancestral societies were insurance benefits for dominants, headstart benefits for subordinates and direct reproduction for both. The two lineages where morphologically distinct foraging worker castes evolved both occur in ecosystems with severe constraints on independent nesting and where brood rearing periods are very seasonally restricted. These conditions would have strongly curtailed dispersal options and increased the likelihood that dominance supersedure occurred after brood rearing opportunities were largely degraded. The origins of foraging castes, therefore, represented a shift towards assured fitness gains by subordinates, mediated by the dual constraints of social hierarchies and environmental harshness.