玉米隐花色素CRY1b和CRY2基因转录丰度对不同光质处理的响应

Transcription Abundances of CRY1b and CRY2 Genes in Response to Different Light Treatments in Maize

玉米株高、开花期、产量、品质等性状与环境中的光密切相关。隐花色素是一类蓝光和近紫外光的受体,主要参与植物的光形态建成及动、植物的生物钟调控。通过研究玉米隐花色素基因对不同光处理的表达模式,可为进一步研究其对玉米光形态建成的作用奠定基础。本研究采用RT-PCR技术克隆了玉米Zm CRY1b和Zm CRY2基因;利用生物信息学相关网站和软件对其编码蛋白的结构域及氨基酸进行了系统发育分析;利用q RT-PCR分析了玉米自交系B73中Zm CRY1b和Zm CRY2基因在不同组织、以及响应不同光质及长日照和短日照处理的转录丰度。研究发现,玉米与拟南芥、水稻和小麦的CRY蛋白有相同的结构域及较高的氨基酸序列的一致性,表明它们具有相似的功能。Zm CRY1b和Zm CRY2基因主要在玉米的叶片中表达;二者能迅速响应各种持续光质、黑暗到不同光质转换及长日照和短日照处理,且Zm CRY1b在各种处理下的转录丰度均高于Zm CRY2,可能暗示Zm CRY1b在玉米中功能更强。以上研究结果表明,Zm CRY1b和Zm CRY2基因均能有效地响应各种光质和光周期处理,并在玉米的光形态建成中发挥重要作用。本研究为进一步探明Zm CRY1b和Zm CRY2基因的功能及其在玉米品种改良中的应用提供了研究基础。

Light is lightly related to the important agronomic traits in maize such as plant height,flowering time,yield and quality.Cryptochromes are blue and ultraviolet-A photoreceptors generally existing in animal,plant and microbial,which mainly regulate photomorphogenesis in plants and circadian rhythms in both of plant and animal.Therefore,the expression pattern analysis of cryptochrome in maize could lay a research foundation in the photomorphogenesis in maize.The ZmCRY1b and ZmCRY2 genes were cloned by RT-PCR.Their proteins’function domains and the phylogenetic analysis of amino acid sequences were carried out through bioinformatics analysis.The transcription abundances of ZmCRY1b and ZmCRY2 genes in different tissues of inbred line B73 under different light treatments were analyzed by qRT-PCR.We found that the function domains of ZmCRY1b or ZmCRY2 protein was consistent with CRY1 or CRY2 in Arabidopsis,rice and wheat,which contains the PHR and CCE domains or the PHR domain,respectively.Phylogenetic analysis indicated that the three gramineous CRYs from maize,wheat,and rice belonged to the same branch,while showing low similarity to other CRY1 proteins from dicotyledons.ZmCRY1b and ZmCRY2 genes highly expressed in leaf.Meanwhile,they could respond to all treatments of different continuous light conditions,the transitions from the dark to light conditions,as well as long-day and short-day conditions.The transcription abundances of ZmCRY1b in all treatments were higher than those of ZmCRY2,indicating that ZmCRY1b was more important than ZmCRY2 in maize.In conclusion,both of ZmCRY1b and ZmCRY2 genes can greatly respond to different light conditions and light cycle treatments,and play an important role in maize photomorphogenesis.Our results also provide a research basis for functional exploration of ZmCRY1b and ZmCRY2 in crop improvement.