Transcriptome profiling of differentially expressed genes in cytoplasmic male-sterile line and its fertility restorer line in pigeon pea (Cajanus cajan L.)

Abstract

Background: Pigeon pea (Cajanus cajan L.) is the sixth major legume crop widely cultivated in the Indian sub-continent, Africa, and Southeast Asia. Cytoplasmic male-sterility (CMS) is the incompetence of flowering plants to produce viable pollens during anther development. CMS has been extensively utilized for commercial hybrid seeds production in pigeon pea. However, the molecular basis governing CMS in pigeon pea remains unclear and undetermined. In this study transcriptome analysis for exploring differentially expressed genes (DEGs) between cytoplasmic male-sterile line (AKCMS11) and its fertility restorer line (AKPR303) was performed using Illumina paired-end sequencing. Results: A total of 3167 DEGs were identified, of which 1432 were up-regulated and 1390 were down-regulated in AKCMS11 in comparison to AKPR303. By querying, all the 3167 DEGs against TAIR database, 34 pigeon pea homologous genes were identified, few involved in pollen development (EMS1, MS1, ARF17) and encoding MYB and bHLH transcription factors with lower expression in the sterile buds, implying their possible role in pollen sterility. Many of these DEGs implicated in carbon metabolism, tricarboxylic acid cycle (TCA), oxidative phosphorylation and elimination of reactive oxygen species (ROS) showed reduced expression in the AKCMS11 (sterile) buds. Conclusion: The comparative transcriptome findings suggest the potential role of these DEGs in pollen development or abortion, pointing towards their involvement in cytoplasmic male-sterility in pigeon pea. The candidate DEGs identified in this investigation will be highly significant for further research, as they could lend a comprehensive basis in unravelling the molecular mechanism governing CMS in pigeon pea.

Global gene expression analysis of pigeonpea with male sterility conditioned by A2 cytoplasm

“…Based on GO, BiNGO, and KEGG analysis we could establish a possible connection of CMS trait of pigeonpea with perturbations in glucose and lipid metabolism, energy deficiency, pollen development and pollen tube growth, and ROS generation and PCD. Our findings are congruent with a previous report in pigeonpea (Saxena et al., 2020) and similar mechanisms reported in other crops. Our findings offer a comprehensive foundation to accelerate functional genomics of CMS trait of pigeonpea.…”

“…(2017) also associated pollen viability in pigeonpea with impairments in boron homeostasis, which concurs with our observation on differential expression of boron transporters ( C.cajan_04911, C.cajan_39524 ) between the two lines. Consistent with earlier reports, we observed lower expression of arabinogalactan glycoproteins (AGPs), such as GPI‐anchored proteins and Fasciclin‐like arabinogalactan protein 3, in the CMS line, suggesting their participation in impaired microspore development (Rhee et al., 2015; Saxena et al., 2020).…”

Transcriptome Profiling Reveals Molecular Changes during Flower Development between Male Sterile and Fertile Chinese Cabbage (Brassica rapa ssp. pekinensis) Lines

“…Previous studies also reported that the AP2 gene family is highly active in pollen fertility in various plants. However their specific gene functions and regulatory networks are yet to be investigated [54,55]. The bHLH proteins bind to the specific DNA target sites and play a critical role in programmed cell death (PCD) and pollen development [56].…”

Genome-Wide Analysis of the Phospholipase D Family in Five Cotton Species, and Potential Role of GhPLD2 in Fiber Development and Anther Dehiscence

“…Male sterility is a common phenomenon in flowering plant species, occurring in several crops (Liu et al, 2014;Li et al, 2016;Chen et al, 2020b;Saxena et al, 2020). Flowering plants require normal anther dehiscence to ensure timely pollen release at fruit-setting stages.…”