Comparative transcriptome profiling of multi-ovary wheat under heterogeneous cytoplasm suppression

Abstract

DUOII is a multi-ovary wheat line with two or three pistils and three stamens in each floret. The multi-ovary trait of DUOII is controlled by a dominant gene, whose expression can be suppressed by the heterogeneous cytoplasm of TeZhiI (TZI), a line with the nucleus of common wheat and the cytoplasm of Aegilops . DUOII (♀) × TZI (♂) shows multi-ovary trait, while TZI (♀) × DUOII (♂) shows mono-ovary. Observing the developmental process, we found that the critical stage of additional pistil primordium development was when the young spikes were 2–6 mm long. To elucidate the molecular mechanisms that are responsible for the heterogeneous cytoplasmic suppression of the multi-ovary gene, we RNA-sequenced the entire transcriptome of 2–6 mm long young spikes obtained from the reciprocal crosses between DUOII and TZI. A total of 600 differentially expressed genes (DEGs) was identified. Functional annotation of these DEGs showed that the heterogeneous cytoplasmic suppression of additional pistil development mainly involved four pathways, i.e., chloroplast metabolism, DNA replication and repair, hormone signal transduction, and trehalose-6-phosphate in the primordium development stage, which cooperated to modulate the multi-ovary gene expression under heterogeneous cytoplasmic suppression.

Comparative Metabolomic Analysis of Multi-Ovary Wheat under Heterogeneous Cytoplasm Suppression

“…We demonstrated that chloroplast metabolism plays a vital role in cytoplasmic suppression of multi-ovary trait. This discovery corroborated our previous transcriptomic and proteomic analyses [10,11]. In both studies, we found that chloroplast metabolism was altered in TZI × DUOII, which might transmit signal to nucleus and trigger some changes, and these changes then influenced the development of additional pistil primordia and resulted in the suppression of multi-ovary trait.…”

“…The genetic basis of the multi-ovary trait of DUOII has been clarified. However, little is known about the mechanism by which TZI suppresses the expression of the multi-ovary gene in common wheat, although we have studied this process through genomic DNA methylation [9], transcriptomic [10] and proteomic [11] analyses.…”