菠萝SLF/SFB基因家族全基因组鉴定与表达分析  

Genome-wide Identification and Expressions Analysis of SLF/SFB Gene Family in Pineapple

作　　者：井敏敏 李小针 李栋梁[1] 戴小红[1] 顾帅磊 马朝明[1] 陈志辉[1] 陈晶晶[1] JING Minmin;LI Xiaozhen;LI Dongliang;DAI Xiaohong;GU Shuailei;MA Chaoming;CHEN Zhihui;CHEN Jingjing(South Subtropical Crops Research Institute,Chinese Academy of Tropical Agricultural Sciences/National Field Genebank for Tropical Fruit(Zhanjiang)/Key Laboratory of Tropical Fruit Tree Biology,Ministry of Agriculture and Rural Affairs,Zhanjiang,Guangdong 524091,China)

机构地区：[1]中国热带农业科学院南亚热带作物研究所/国家热带果树种质资源圃(湛江)/农业农村部热带果树生物学重点实验室,广东湛江524091

出　　处：《热带作物学报》2023年第7期1317-1327,共11页Chinese Journal of Tropical Crops

基　　金：国家重点研发计划专项(No.2019YFD1001104);海南省自然科学基金项目(No.322QN377);农业农村部物种品种资源保护项目(No.125163006000160001)。

摘　　要：自交不亲和性是高等植物通过抑制自花授粉来阻止近亲繁殖的一种繁殖机制。在以茄科、蔷薇科、车前草科为代表的配子体自交不亲和机制中,花粉和雌蕊之间的自我/非自我识别由多态性S位点决定,其中SLF(S-locus F-box)/SFB(S-haplotype-specific F-box)基因是配子体自交不亲和花粉S决定因子。本研究通过生物信息学方法从菠萝基因组中筛选鉴定出21个SLF/SFB家族基因(AcSLF1~AcSLF21),各AcSLF基因在N端具有F-box保守结构域,其氨基酸长度、理论等电点、分子量存在较大差异,编码氨基酸序列大小范围为242~612 aa,分子量为27.778~69.070 kDa,其中18个AcSLFs蛋白偏碱性,总体蛋白稳定性较差,预测18个AcSLFs蛋白亚细胞定位于细胞核中,蛋白二级结构60%以上由α-螺旋和无规则卷曲组成。通过染色体定位分析发现其不均匀地分布在14条染色体上,其中AcSLF21未定位到具体染色体位置,并发现AcSLF4、AcSLF5、AcSLF6、AcSLF8、AcSLF14和AcSLF15与菠萝RNaseT2家族基因发生连锁。从进化关系中发现,菠萝SLF/SFB家族与蔷薇科、车前科、茄科植物SLF/SFB进化关系较远。利用qRT-PCR对AcSLFs基因在菠萝雌蕊、雄蕊、叶片、果肉、茎和根的表达量进行分析,结果发现AcSLFs基因在菠萝不同组织中具有明显的表达差异性,其中AcSLF1、AcSLF2、AcSLF4、AcSLF9、AcSLF10、AcSLF11、AcSLF15、AcSLF19、AcSLF20、AcSLF21基因在菠萝雄蕊中呈高表达量,AcSLF3、AcSLF7在果肉中表达量最高,AcSLF5、AcSLF12、AcSLF18在根中表达量显著高于其他组织,总体来说,大部分菠萝AcSLFs基因主要在菠萝雄蕊或叶片中高表达。同时分析了雌蕊自花、异花授粉前后的表达变化,发现AcSLF1、AcSLF2、AcSLF15三个基因在授粉雌蕊中的表达量较未授粉显著上调,尤其在授粉6h表达量急剧上调,随着花粉管的伸长其表达量降低,但在授粉24h仍具有较高的表达量,推测这些基因可能在菠萝自交不亲Self-incompatibility is a genetic mechanism to prevent self-fertilization and the consequent inbreeding and fitness decay in plant populations.In the gametophyte self-incompatibility mechanism represented by Solanaceae,Rosaceae and Plantaginaceae,the self/non-self recognition between pollen and pistil is determined by the polymorphic S locus.SLF(S-locus F-box)/SFB(S-haplotype-specific F-box)gene is the pollen S determinant of gametophyte self-incompatibility.In this study,21 SLF/SFB family genes were screened and identified based on the genome-wide of the pineapple.Each AcSLF gene had an F-box conserved domain at the N-terminal.There were great differences in amino acid length,theoretical isoelectric point and molecular weight.The size range of the encoded amino acid se-quence was 242-612 aa,and the molecular weight was 27.778-69.070 kDa.The isoelectric point ranged from 5.70 to 9.57.18 AcSLF proteins were alkaline and most proteins were unstability,only AcSLF19,AcSLF21 were stability.It was predicted that 18 AcSLF proteins were located in the nucleus,one AcSLF protein in chloroplast,two AcSLF protein in both chloroplast and nucleus,and more than 60%of the secondary structure of the protein was composed of alpha helix and random coil.Bioinformatics analysis showed that the pineapple SLF/SFB family genes,which were unevenly distributed on 14 chromosomes,and the chromosome location of AcSLF21 was undetermined.Furthermore,AcSLF4,AcSLF5,AcSLF6,AcSLF8,AcSLF14 and AcSLF15 were linked with RNase T2 family genes,this was one of the main characteristics of pollen SLF gene.AcSLF genes contained different numbers of introns,most of which contained 1~2 introns,and AcSLF3 contained 4 introns.Based on the above analysis results,it showed that AcSLF proteins had dif-ferent characteristics.Phylogenetic analysis indicated that the evolutionary relationship of AcSLFs in pineapple was far away from the SLF/SFB in Rosaceae,Plantaginaceae and Solanaceae,the degree of clustering was low on the branches of evolutionary tree.The express

关 键 词：菠萝 SLF/SFB基因家族 生物信息学 表达量分析 

分 类 号：S668.3[农业科学—果树学]