低温胁迫下香菇基因表达差异研究

香菇为变温结实型担子菌,为探讨低温胁迫诱导香菇子实体形成的分子机理,应用mRNA差异显示技术对低温胁迫下香菇菌丝体基因表达差异进行了比较.电泳差异展示结果表明,低温胁迫前后基因表达在数量水平和质量水平上都存在显著差异,数量水平的差异表现为低温胁迫过程中表达序列标签(expressed sequence tags,ESTs)增强表达或减弱表达;质量水平上的差异表现为低温胁迫使部分ESTs特异诱导表达或沉默表达.差异ESTs的类型比较和多态性分析发现,低温胁迫处理6~12h可能是诱发香菇原基发生的关键时段.本文还对显著差异表达的基因片段进行序列分析和Northern杂交验证,初步讨论了低温胁迫时间在调控香菇子实体发生中的作用.图4表2参13

Differences of Gene Expression in Mycelia of Lentinula edodes under Cold Stress

Lentinula edodes (Berk.) Pegler is a kind of important edible fungus, its fruiting body development depends on temperature alterations, and cold stress is a key environmental factor for its fruiting body inducement.The identification of gene expression differences under cold stress makes a better understanding of shiitake morphogenesis.Analysis of the differences in gene expression during cold stress by means of mRNA-differential display indicated that gene expression of the control was obviously altered both in quantity and quality.Quantitatively, there were enhanced or depressed expressions of genes during cold stress with genetic expression trend forwards the control.Qualitatively, the mycelia could have specific gene expression or silent expression induced by cold stress.The comparison of expression type and polymorphisms of differential display ESTs showed that a cold stress of 6~12 h was a key treatment in primordial initiation.And the relationship between the differential display ESTs under cold stress and fruiting body development was also illustrated. Fig 4, Tab 2, Ref 13