向日葵MADS-Box基因HAM23-like克隆和表达分析

Cloning and Expression Analysis of MADS-box Gene HAM23-like in Helianthus annuus

摘要:

为了解MADS-box基因在向日葵（Helianthus annuus）花发育过程中的作用，采用RT-PCR技术克隆了1个MADS-box基因新成员HAM23-like，开放阅读框为831 bp，编码276个氨基酸，相对分子量为30.52 kD，理论等电点为9.42。系统发育分析表明，HAM23-like与拟南芥的AGL18聚于同一分支，具有较近的亲缘关系。qRT-PCR分析表明，HAM23-like基因在花和成熟果实（籽粒饱满期）中的表达量较高；HAM23-like在开花当天的雄蕊中的表达量最高；随着花的发育，HAM 23-like表达量逐渐升高，在开花后5 d （果实形成早期）达到最高表达水平。因此，推断HAM23-like基因可能与向日葵花器官后期发育和瘦果早期发育相关。

Abstract:

MADS-box family proteins are important transcription factors associated with the regulation of growth and development, especially in floral development of higher plants. HAM23-like, a new member of the MADS-box genes, was cloned from Helianthus annuus. The bioinformatic results revealed that HAM23-like gene had an open reading frame of 831 bp, encoding a protein with 276 amino acid; the protein possessed a relative molecular weight of 30.52 kD and a theoretical isoelectric point of 9.42. The analysis of phylogenetic tree showed that HAM23-like was closely homologous to the AGL18 gene of Arabidopsis thaliana. Moreover, the qRT-PCR results indicated that the HAM 23-like gene were highly expressed in flower and mature fruit in tissue expression pattern, and in different floral organ of flowering day, the expression of HAM23-like reached the highest level in stamen. In addition, the expression of the HAM23-like gene was gradually raised during the floral development, and reached the highest expression on 5 days after flower blooming. These results implied that HAM23-like gene would be involved in the later stage of floral organs development and the earlier stage of achene development in H. annuus. The results of this study could provide some preliminary data and theoretical basis for further study, especially, it will help to explore the regulatory role of HAM23-like in floral development and achene formation in H. annuus.