ERF转录因子调控生物胁迫反应的研究进展

ERF家族是植物所特有的APETALA2/乙烯响应因子(APETALA2/ethylene-responsive factor,AP2/ERF)转录因子家族的一个主要亚家族,其成员结构特点是仅含有1个58-60个氨基酸组成的AP2/ERF结构域.有关该家族成员的大多数研究集中在与寒、旱等非生物胁迫方面,最近越来越多的研...     

MYB类转录因子对花药和花粉发育的调控途径

花药发育和花粉形成的各个步骤由众多基因控制,一些转录因子通过调控花药发育相关基因的表达,是功能性花粉形成的关键因子。MYB类转录因子作为植物中最大的转录因子家族,是其中非常重要的一类转录因子。该文结合近年来国内外有关被子植物花粉发育相关MYB转录因子在花药发育和花粉形成的调控途径,包括绒毡层发育、胼胝质的沉积和降解、光合产物的运输、花药的开裂以及雄配子体形成过程中所起的重要作用等方面的研究进展,重点对MYB类转录因子通过形成对绒毡层发育、同化物分配、苯丙烷物质代谢等相关靶位基因的控制网络,转录调控植物花粉发育和花药开裂过程等研究进行综述讨论。     

转录因子与microRNA在基因表达调控中的功能联系及差异

转录因子和微RNA(microRNA)是最大的两类反式作用因子,它们是基因表达调控的重要调控因子.它们协调发挥调控作用,精细调控基因的表达,在细胞分化和动物生长发育过程中发挥重要的作用.随着对转录因子和microRNA研究的深入,人们发现转录因子和microRNA在基因表达调控网络中关系紧密,它们的分子作用机制有许多相似之处,两者都通过各自的顺式作用元件调控基因表达,且作用的方式类似.但转录因子和microRNA也存在不同之处,转录因子既可以激活基因表达,也可抑制基因表达,而microRNA主要是抑制基因表达.另外,转录因子调控区的复杂性一般高于microRNA的调控区域.本文综述了转录因子和microRNA的异同点,并提出了未来转录因子和microRNA的研究方向.     

Studies on the Salicylic Acid Inducted Lipid Peroxidation and Defense Gene Expression in Tobacco Cell Culture

Salicylic acid (SA) could inhibit catalase activity, induce rapid lipid peroxidation and PR-1 gene expression of the tobacco ( Nicotiana tabacum L. ) cell culture which was incubated with exogenous SA. Ρ-ihydroxybenzene and H2O2 could also induce lipid peroxidation and PR-1 gene expression at different level, but they were not able to inhibit the catalase activity of tobacco cells. Inhi0itors of mRNA and protein-synthesis (a-amanitine and cycloheximide, respectively) could not induce both lipid peroxidation and PR-1 gene expression of tobacco cell culture. However, coordinated action with SA respectively, a-amanitine or cycloheximide was able to induce lipid peroxidation effectively, but strongly blocked the activation of PR-1 gene expression by SA in tobacco cell culture. These results suggested that the generation of reactive metabolites or free radicals, which were induced by SA or other inducers through reaction with catalase or other compounds, initiated lipid peroxidation, subsequently activated pathogen-resistance genes expression. Obviously the lipid peroxidation molecule played an important role in SA signal transduction in tobacco.     

The Role of GAMYB Transcription Factors in GA-Regulated Gene Expression

A gibberellin- and abscisic acid-regulated MYB, GAMYB, was first identified as an activator of GA-regulated genes in cereal aleurone. Here we review recent advances made in delineating the signaling events related to GAMYB expression and function in aleurone. In addition, there is a growing body of evidence that GAMYB plays an important role in other aspects of plant growth and development, including anther development, stem elongation, floral initiation and seed development.