Characterization of small RNAs and genes in maize anthers (ms23 sterile)

ABSTRACT: Successful male gametogenesis involves orchestration of sequential gene regulation for somatic differentiation in pre-meiotic anthers. We report here the cloning of Male Sterile23 (Ms23), encoding an anther-specific predicted basic helix-loop-helix (bHLH) transcription factor required for tapetal differentiation; transcripts localize initially to the precursor secondary parietal cells then predominantly to daughter tapetal cells. In knockout ms23-ref mutant anthers, five instead of the normal four wall layers are observed. Microarray transcript profiling demonstrates a more severe developmental disruption in ms23-ref than in ms32 anthers, which possess a different bHLH defect. RNA-seq and proteomics data together with yeast two-hybrid assays suggest that MS23 along with MS32, bHLH122, and bHLH51 act sequentially as either homo- or heterodimers to choreograph tapetal development. Among them, MS23 is the earliest-acting factor, upstream of bHLH51 and bHLH122, controlling tapetal specification and maturation. In contrast, MS32 is constitutive and independently regulated and is required later than MS23 in tapetal differentiation. We characterized a maize (Zea mays) mutant line, ms23-ref, which the tapetal cells lack a dense cytoplasm and are not Binucleate -- the two characteristics of normal TP during meiosis. The meiocytes in ms23-ref fail to progress beyond meiotic prophase I. By profiling the small RNA population in ms23 mutants, we investigated the impact of ms23 mutation on small RNAs abundance in 0.4 mm, 0.7 mm, 1.0 mm, 1.5 mm and 2.0 mm anther. We also investigated the transcript abundance that were impacted in ms23 mutant by transcriptome profiling. The result provides an avenue for future research to understand the genetic networks and protein interactions among ms23, important for tapetal development in maize anther.

ORGANISM(S): Zea mays

PROVIDER: GSE90849 | GEO | 2016/12/05

SECONDARY ACCESSION(S): PRJNA356172

REPOSITORIES: GEO