目的 生长素应答因子（auxin response factors，ARFs）基因家族参与颠茄Atropa belladonna生长发育的调控，对颠茄ARF基因（AbARF）进行全基因组鉴定及表达特征分析。方法 基于已发布的颠茄全基因组，利用生物信息学方法对AbARF基因家族成员进行鉴定并对其理化性质、染色体分布、系统进化、基因结构、顺式作用元件进行分析，利用实时荧光定量PCR（qRT-PCR）分析其在不同温度、光质、组织部位的表达特征。结果 共鉴定出41个AbARF基因（AbARF1～AbARF41），分为4个亚家族，编码的氨基酸长度在603～1 116 aa，蛋白质相对分子质量为68 709.35～125 100.60，等电点介于5.27～8.25，亚细胞定位全部定位于为细胞核。基因结构分析发现所有AbARF基因均含有B3保守结构域，顺式元件预测结果表示光响应元件和脱落酸元件在AbARF基因家族启动子区域分布广泛。基因组内共线性分析表明，全基因组复制和片段性复制在AbARF基因家族进化中发挥了重要作用，复制过后经过了强烈的纯化选择。qRT-PCR表达特征分析结果表明，大部分AbARF在低温（18 ℃）胁迫下表达量显著下调，在白光调控下表达量显著高于红光和黄光，多数AbARF基因在叶中表达量普遍高于主根、侧根、茎和花。结论 从全基因组水平对颠茄ARF基因家族进行鉴定和生物信息学分析，为进一步阐明颠茄ARF基因的功能奠定基础。

Objective The auxin response factors (ARFs) gene family is involved in the regulation of growth and development of Atropa belladonna. Genome-wide identification and expression profile analysis of the belladonna ARF gene (AbARF) can lay a scientific foundation for elucidating the growth and development functions and mechanism of the AbARF gene family. Methods Based on the published whole genome data of A. belladonna, bioinformatics methods were used to identify the AbARF gene family members and analyze their physical and chemical properties, chromosomal distribution, phylogenetic evolution, gene structure, and cis-acting elements, using real-time PCR (qRT-PCR) to analyze its expression characteristics at different temperatures, light quality, and tissue locations. Results A total of 41 A. belladonna ARF genes (AbARF1—AbARF41) were identified, divided into four subfamilies, The length of the encoded amino acids ranges from 603 to 1 116 aa, the relative molecular mass of the protein is 68 709.35 to 125 100.60, the protein isoelectric point ranges from 5.27 to 8.25, and all subcellular locations are located in the nucleus. Gene structure analysis found that all ARF proteins contain the B3 conserved domain, the prediction results of cis-elements indicate that light-responsive elements and abscisic acid elements are widely distributed in the promoter region of the AbARF gene family. Intra-genomic collinearity analysis showed that whole-genome duplication and segmental duplication played an important role in the evolution of the AbARF gene family, and that duplication underwent strong purifying selection. The results of qPCR expression profile analysis showed that the expression levels of most AbARFs were significantly down-regulated under low temperature (18 ℃) stress. The expression levels under white light regulation were significantly higher than those under red and yellow light. The expression levels of most AbARF genes in leaves were generally higher than those in main roots, lateral roots, stems, and flowers. Conclusion Identification and bioinformatics analysis of the ARF gene family at the whole genome level will lay the foundation for further elucidating the function of the A. belladonna ARF genes.

R286.12

国家自然科学基金资助项目(82104329,32401226);中国博士后科学基金特别资助项目(2014T170252);河南省科技攻关(242102310549);河南省重点研发专项(231111312700,241111310200);河南省国际科技合作项目(242102521056)