Comparative transcript profiling of alloplasmic male-sterile lines revealed altered gene expression related to pollen development in rice (Oryza sativa L.).

Jihong Hu,Guanglong Chen,Yi Ding,Qian Qian,Hongyuan Zhang

doi:10.1186/s12870-016-0864-7

Abstract

BackgroundCytoplasmic male sterility (CMS) is an ideal model for investigating the mitochondrial-nuclear interaction and down-regulated genes in CMS lines which might be the candidate genes for pollen development in rice. In this study, a set of rice alloplasmic sporophytic CMS lines was obtained by successive backcrossing of Meixiang B, with three different cytoplasmic types: D62A (D type), ZS97A (WA type) and XQZ-A (DA type).ResultsUsing microarray, the anther transcript profiles of the three indica rice CMS lines revealed 622 differentially expressed genes (DEGs) in each of the three CMS lines compared with the maintainer line Meixiang B. GO and MapMan analysis indicated that these DEGs were mainly involved in lipid metabolism and cell wall organization. Compared with the gene expression of sporophytic and gametophytic CMS lines, 303 DEGs were identified and 56 of them were down-regulated in all the CMS lines of rice. These down-regulated DEGs in the CMS lines were found to be involved in tapetum or cell wall formation and their suppressed expression might be related to male sterility. Weighted gene co-expression network analysis (WGCNA) revealed that two modules were significantly associated with male sterility and many hub genes that were differentially expressed in the CMS lines.ConclusionA large set of putative genes involved in anther development was identified in the present study. The results will give some information for the nuclear gene regulation by different cytoplasmic genotypes and provide a rich resource for further functional research on the pollen development in rice.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-016-0864-7) contains supplementary material, which is available to authorized users.

Highlights

Cytoplasmic male sterility (CMS) is an ideal model for investigating the mitochondrial-nuclear interaction and down-regulated genes in CMS lines which might be the candidate genes for pollen development in rice
These results showed that mitochondrial genomic organization was different among the three CMS lines and Meixiang B (MB)
The results indicated that DA-CMS and D-CMS may have a similar mechanism for pollen abortion, which was different from wild abortive (WA)-CMS

Summary

Introduction

Cytoplasmic male sterility (CMS) is an ideal model for investigating the mitochondrial-nuclear interaction and down-regulated genes in CMS lines which might be the candidate genes for pollen development in rice. In the past few decades, many types of CMS lines have been developed and used in hybrid breeding in China, such as wild abortive (WA) type, dwarf-wild-abortive (DA) type, Honglian (HL) type, Dissi (D) type, Indonesia paddy (ID) type and Maxie type and so on [4, 5]. Many of these CMS lines are sporophytic and their pollen grains are irregularly shaped and unstainable with 1 % I2–KI solution [4]. Xieqingzao A (XQZ-A), a DA-CMS line, originated from dwarf wild rice in Jiangxi, China and its anther is small without cracking [6]

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Discussion

Conclusion