中药火麻仁基原植物大麻LBD基因家族成员的鉴定与表达分析

Genome-wide analysis of LBD(lateral organ boundaries domain) gene family in Cannabis sativa of traditional Chinese medicine hemp seed

LBD(lateral organ boundaries)转录因子在植物生长发育和次生代谢调控中起着重要作用。为了发掘大麻LBD基因的功能,该研究在基因组和转录组水平上利用生物信息学手段,对大麻LBD基因家族进行系统鉴定,并对其表达模式进行分析。结果表明,大麻LBD基因家族含有32个成员,可分成2大类,7亚族,ClassⅠ分为5个亚族分别是ClassⅠ_a至ClassⅠ_e,ClassⅡ分为2个亚族分别是ClassⅡ_a和ClassⅡ_b;理化性质分析显示,大麻LBD基因家族编码的氨基酸数目为172~356,等电点为4.92~9.43,相对分子质量为18 862.92~40 081.33,大部分成员定位于细胞核中;染色体定位显示32个成员不均一地分布在大麻的10条染色体上;LBD转录因子结构域、基因结构和Motifs相对保守,不同类成员特征相近;基因上游启动子区含有多种植物激素及环境因子相关的顺式作用元件,表明LBD基因的表达可能会受到激素和外界环境因素的诱导;大麻LBD基因在ZYS品种(低四氢大麻酚,高二氢大麻酚)茎、叶、花的表达模式不同,LBD基因家族成员主要在ZYS品种的花和茎中表达,而在叶中表达的成员很少;ClassⅡ成员CsLBD21和CsLBD23在花和茎中表达,CsLBD8和CsLBD18在花、茎和叶中均有表达,这些基因可能参与大麻的生长发育发育进而影响大麻素的生物合成。该研究为后续大麻LBD基因家族的功能研究奠定了基础。

LBD(lateral organ boundaries)transcription factors play an important role in the regulation of plant growth, development and secondary metabolism. In order to explore the function of LBD genes in cannabis, the Cannabis sativa genome and transcriptome were used to identify the C. sativa LBD gene family, and analyzed their expression patterns. Our results showed that the cannabis LBD contains 32 members, which were divided into two major categories, seven sub-families. Class Ⅰ was divided into 5 sub-families, named Class Ⅰ_a to Class Ⅰ_e, while Class Ⅱ was divided into 2 sub-families, including Class Ⅱ_a and Class Ⅱ_b. Analysis showed that the number of amino acids encoded LBDs was between 172 and 356, and the isoelectric point was between 4.92 and 9.43. The mole-cular weight of LBD was between 18 862.92 Da and 40 081.33 Da, and most members are located in the nucleus. Chromosome positioning of LBD showed that 32 members were unevenly distributed on 10 chromosomes of C. sativa LBD transcription factor domain, gene structure and motifs are relatively conservative, and the characteristics of different class members are similar. The upstream promoter region of the gene contains a variety of cis-acting elements related to plant hormones and environmental factors, C. sativa LBD genes have different expression patterns in the stems, leaves, and flowers of ZYS varieties(low tetrahydrocannabinol, high cannabidiol). The members of the LBD gene family are mainly expressed in the flowers and stems of ZYS varieties, while members expressed in the leaves very few;Class Ⅱ members CsLBD21 and CsLBD23 are expressed in flowers and stems, and CsLBD8 and CsLBD18 are expressed in flowers, stems and leaves. These genes may participate in the growth and development of cannabis and affect the biosynthesis of cannabinoids. This study laid the foundation for the subsequently functional research of the cannabis LBD gene family.