橡胶树HbWD40基因家族的全基因组分析

Genome-wide analysis of Hb WD40 gene family in rubber tree

WD40是一类支架蛋白,广泛参与植物的生长发育、花青素的生物合成以及生物和非生物胁迫等生命活动。利用生物信息学技术,本研究从橡胶树基因组中鉴定到258个HbWD40家族成员,并对其染色体分布、蛋白保守结构域、组织特异性表达以及低温胁迫下的表达模式进行系统分析。结果显示, HbWD40成员在18条染色体上均有分布;根据结构域的不同可将HbWD40家族划分为28个亚族;表达模式分析发现有175个成员在所有5个组织中均有表达,并鉴定到8个在低温胁迫下差异表达的成员。利用RT-PCR技术克隆了橡胶树的HbWD40-168基因。该基因CDS长1 335 bp,编码444个氨基酸。保守结构域分析显示HbWD40-168含有4个WD40重复元件和2个ZnF_C3H1锌指蛋白结构域。启动子分析显示HbWD40-168启动子区域存在多种激素或胁迫相关顺式作用元件。亚细胞定位显示HbWD40-168定位于细胞核。本研究为深入鉴定HbWD40家族在橡胶树中的生物学功能提供基础。

WD40 is a kind of scaffold protein, which is widely involved in various processes such as plant growth and development, anthocyanin biosynthesis, and biotic/abiotic stresses. Using bioinformatics technology, we identified 258 HbWD40 family members from the rubber tree(Hevea brasiliensis) genome,and systematically analyzed their chromosomal distribution, protein conserved domains, tissue-specific expression, and expression patterns under low temperature stress. The results showed that HbWD40members were distributed on all 18 chromosomes;the HbWD40 family could be divided into 28 subfamilies according to different conserved domains. The results of expression pattern showed that 175 members were expressed in all 5 tissues, and 8 differentially expressed members were identified under low temperature stress. We further cloned HbWD40-168 gene by RT-PCR technique. The coding sequence(CDS) of this gene was 1 335 bp in length, encoding a putative protein of 444 amino acids. Conserved domain analysis showed that HbWD40-168 contained four WD40 repeat elements and two ZnF_C3H1 zinc finger protein domains. Promoter analysis revealed the presence of multiple hormone-or stress-related cis-acting elements in the promoter region of HbWD40-168. Subcellular localization showed that HbWD40-168 localized in the nucleus. This study provides a basis for in-depth identification of the biological functions of the HbWD40 family in rubber trees.