Gene characterization and molecular pathway analysis of reverse thermosensitive genic male sterility in eggplant (Solanum melongena L.)

Abstract

The naturally occurring mutant eggplant line 05ms was identified with reverse thermosensitive genic male sterility (rTGMS), but its temperature-responsive fertility mechanisms remain largely unknown. Here, we studied the flower morphology, anther cellular structure, and genome-wide gene expression of this rTGMS line. Candidate genes for thermosensitive male sterility during the microspore development of 05ms and the temperature-insensitive line S63 under low-temperature (LT) and high-temperature (HT) conditions were identified. Under LT, tapetum cells were vacuolated and had delayed disintegration in 05ms. RNA-seq analysis indicated that DEGs were enriched in the KEGG pathways ‘plant hormone signal transduction’, ‘starch and sucrose metabolism’, and ‘phenylpropanoid biosynthesis’. We identified two genes, 4CLL1 (Sme2.5_00368.1_g00010.1) and CKI1 (Sme2.5_10056.1_g00002.1), which could potentially regulate eggplant anther development and may be candidate genes for rTGMS. Finally, we propose a working model of anther abortion for rTGMS in eggplant. CKI1 responds to LT stress and causes expression changes in genes related to anther development, such as 4CLL1, and the cellular structure of the tapetum becomes abnormal, causing male sterility. The findings of this study explain the underlying molecular mechanisms of male sterility in eggplant rTGMS lines.

Unraveling Cadmium Toxicity in Trifolium repens L. Seedling: Insight into Regulatory Mechanisms Using Comparative Transcriptomics Combined with Physiological Analyses

“…In our study, 8 DEGs (PAL, C4H, CCR, and LAC) were up-regulated in roots related to lignin biosynthesis and achieved the highest expression level after 3 h Cd treatment. Increased lignin synthesis in roots to block Cd into the plant cells has also been identified in Vicia sativa [50], Brassica chinensis (B. chinensis) [47], Solanum melongena [51], Nicotiana species [52], and S. nigrum [10] under Cd stress. In addition, POD could regulate the biosynthesis of lignin and the related genes were upregulated in our studies [37,48].…”

High Temperature-induced Spindle Destabilization Results in Aborted Pollen Production in Populus

“…Many previous studies have shown that heat stress can lead to male sterility in Oryza sativa L., Solanum melongena L., and Solanum lycopersicum Lam 44,45 . For example, in heat-susceptible rice plants, heat stress lasting 4 days or longer during the early phase of anther development caused the premature degradation of tapetum cells and PCD, leading to complete male sterility 46, 47 .…”

Genomics and Marker-Assisted Improvement of Vegetable Crops

“…Furthermore, two independent dominant fertility restorer (Rf) genes have been discovered, sequenced, and found tightly linked to a SCAR marker (Hasnunnahar et al, 2012). More recently, through an RNA-seq approach, further genes and pathways related to MS in eggplant have been identified (Yang et al, 2018b;Li et al, 2019a). However, the molecular mechanism of MS is not yet fully understood and further effort is needed to integrate MS into various eggplant genetic backgrounds through MAS.…”