生物技术通报2024，Vol.40Issue(7)：125-136,12.DOI:10.13560/j.cnki.biotech.bull.1985.2024-0132
水稻黄化早抽穗突变体hz1的基因鉴定及功能分析
Gene Identification and Functional Analysis of Yellowish and Early Heading Mutant hz1 in Rice
摘要
Abstract
[Objective]The heading date of rice(Oryza sativa)is an important agronomic trait and crucial for the regional adaptability and yields.Identification and functional analysis of heading date-associated genes may provide important gene resources for the breeding in rice.[Method]BSA-seq was performed to identify target gene of a yellowish and early heading mutant huangzao 1(hz1).RT-qPCR was used to analyze the expression profile of target genes.The subcellular localization of HZ1 was determined by transient transformation between rice protoplasts and tobacco cells.Meanwhile,the heading dates,chlorophyll content and hydrogen peroxide content were measured to analyze the phenotype of hz1 mutant.[Result]Field phenotypic observations found that hz1 showed early heading phenotype.The heading date of hz1 mutant was the same under long-day(LD)and short-day(SD)conditions,which were 43 d and 26 d earlier than those of wild type(WT)respectively,indicating that hz1 was a photoperiod-insensitive mutant.Moreover,hz1 demonstrated a yellowish phenotype,with a decrease in chlorophyll content compared with WT.Genetic analysis revealed that hz1 was controlled by a recessive gene.BSA-seq(Bulk segregation analysis with whole-genome sequencing)of F2 pools indicated that the causal gene was linked with molecular markers on the chromosome 6 with 17.8 Mb region.Further analysis demonstrated that LOC_Os06g40080 site with a T-DNA insertion was completely linkage with hz1 mutant.LOC_Os06g40080 site was an identified SE5 gene encoding heme oxygenase 1(HO1).Expression pattern analysis revealed that HZ1/SE5 was highly expressed in the leaves and dhad diurnal rhythm expression.Subcellular localization assay showed that HZ1/SE5 protein was localized in chloroplasts.Gene expression analysis showed that HZ1/SE5 regulated the expression of florigen genes Hd3a and RFT1 to modulate the heading date in rice.In addition,HZ1/SE5 can also regulate the expression of genes associated with chlorophyll synthesis pathway to modulate the change of chlorophyll levels.[Conclusion]hz1 mutant is a photoperiodic insensitive mutant due to the mutation of heme oxygenase gene SE5.HZ1/SE5 may regulate the expression of the florigen genes and chlorophyll synthesis-associated genes to influence the heading date and leaf yellowish in rice.关键词
水稻/黄化早抽穗突变体/基因克隆/血红素加氧酶1Key words
rice/yellowish and early heading mutant/gene cloning/heme oxygenase 1引用本文复制引用
庞梦真,赵晓萌,梁闪闪,张泗举,栾维江,徐汉琴,刘海燕,宋娟,王佳涵,孙丽娜,姬佩梅,尹泽芝,胡又川..水稻黄化早抽穗突变体hz1的基因鉴定及功能分析[J].生物技术通报,2024,40(7):125-136,12.基金项目
国家自然科学基金项目(31770343),天津市水稻产业技术体系创新团队项目(ITTRRS2021100004) （31770343）
