水稻热激转录因子基因在植物激素和非生物环境胁迫条件下的表达谱分析(英文)

Expression Profile Analysis of Rice Heat Shock Transcription Factor (HSF) Genes in Response to Plant Hormones and Abiotic Stresses

热激转录因子(heat shock transcription factor,HSF)是植物热激响应的主要控调因子,在植物对环境胁迫的分子响应中起着重要作用。水稻存在多个热激转录因子基因,但它们在水稻对环境胁迫响应中的具体功能还不十分清楚。通过与已知序列比对,从水稻基因组中鉴别出25个水稻HSF基因。通过对HSF氨基酸序列进行进化树分析,25个水稻HSF可分为A,B和C三类。大部分HSF基因剪接模式单一,8个基因存在选择性剪接。运用Q-PCR技术对24个水稻HSF基因在不同组织以及在激素GA3、KT、ABA和高温、干旱、盐胁迫处理条件下的表达谱进行了分析。大部分基因的表达具有组织特异性。10个HSF基因的表达显著受激素GA3、KT和ABA调控。13个HSF基因明显对高温、干旱和盐胁迫产生表达响应。

Heat shock transcription factors（HSFs）are critical regulators of heat shock response of plants and participate in various plant stress responses.Rice HSFs are encoded by a multigene family but their specific functions are not well-understood.Study on expression profiles of rice HSF genes is important for illuminating the molecular mechanism by which rice respond to environmental stresses.The identification of rice HSFs genes were conducted through sequence comparing and their expression profiles in various tissues under hormone treatments and abiotic environmental stresses were also analyzed.In a genome-wide scan,twenty-five rice HSF genes were identified and called OsHsf1 OsHsf25,respectively.The phylogenetice tree of rice and Arabidopsis HSFs was constructed through amino acid sequence alignment,twenty-five rice HSFs were classified as three groups,class A,B and C,and each group comprised one or several subgroups.Class A,B and C included thirteen,eight and four genes,respectively.The gene structure analysis showed that most rice HSF genes contain a small number of exons and introns,and are spliced into a single gene model,alternative splicing was observed only in eight members（OsHsf2,OsHsf7,OsHsf9,OsHsf11,OsHsf12,OsHsf21,OsHsf24 and OsHsf25）.The expression profiles of 24 rice HSF genes were derived through quantitative PCR.Most rice HSF genes presented the tissue-specific and development-specific transcription patterns.OsHsf4,OsHsf12 and OsHsf13 showed high expression levels in all tissues analyzed,whereas OsHsf17 expressed with low transcription levels.Ten HSF genes were significantly regulated by gibberellin 3（GA3）,kinetin（KT）,and abscisic acid（ABA）treatments at transcription level,among them,OsHsf1,OsHsf3,OsHsf21and OsHsf24 were down-regulated by GA3 and KT,and OsHsf1and OsHsf24 were also up-regulated by ABA.Thirteen HSF genes were observed to have a significant response to drought,salt,and heat stresses.OsHsf1,OsHsf3,OsHsf5,OsHsf11,OsHsf12,OsHsf14,OsHsf21,OsHsf23,OsHsf24,and OsHsf25 were strongly up-regulated by all three stresses.OsHsf2 and OsHsf16 were significantly induced by drought and salt stresses.OsHsf15 was up-regulated only by heat stress.Rice HSFs expression profiles,especially in response to drought,salt,and heat stresses,can provide a foundation for dissecting the functions of rice HSFs in response to abiotic environmental stresses.The HSF genes responding to abiotic stresses identified may be used to improve rice tolerance to abiotic stresses through genetic engineering technology.