Comparative transcriptome profiling of the fertile and sterile flower buds of a dominant genic male sterile line in sesame (Sesamum indicum L.)

Abstract

BackgroundSesame (Sesamum indicum L.) is a globally important oilseed crop with highly-valued oil. Strong hybrid vigor is frequently observed within this crop, which can be exploited by the means of genic male sterility (GMS). We have previously developed a dominant GMS (DGMS) line W1098A that has great potential for the breeding of F1 hybrids. Although it has been genetically and anatomically characterized, the underlying molecular mechanism for male sterility remains unclear and therefore limits the full utilization of such GMS line. In this study, RNA-seq based transcriptome profiling was carried out in two near-isogenic DGMS lines (W1098A and its fertile counterpart, W1098B) to identify differentially expressed genes (DEGs) related to male sterility.ResultsA total of 1,502 significant DEGs were detected, among which 751 were up-regulated and 751 were down-regulated in sterile flower buds. A number of DEGs were implicated in both ethylene and JA synthesis & signaling pathway; the expression of which were either up- or down-regulated in the sterile buds, respectively. Moreover, the majority of NAC and WRKY transcription factors implicated from the DEGs were up-regulated in sterile buds. By querying the Plant Male Reproduction Database, 49 sesame homologous genes were obtained; several of these encode transcription factors (bHLH089, MYB99, and AMS) that showed reduced expression in sterile buds, thus implying the possible role in specifying or determining tapetal fate and development. The predicted effect of allelic variants on the function of their corresponding DEGs highlighted several Insertions/Deletions (InDels), which might be responsible for the phenotype of sterility/fertility in DGMS lines.ConclusionThe present comparative transcriptome study suggested that both hormone signaling pathway and transcription factors control the male sterility of DGMS in sesame. The results also revealed that several InDels located in DEGs prone to cause loss of function, which might contribute to male sterility. These findings provide valuable genomic resources for a deeper insight into the molecular mechanism underlying DGMS.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-016-0934-x) contains supplementary material, which is available to authorized users.

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

“…Over-expression of WRKY 27 showed limited pollen viability leading to male-sterility [113]. In our study, there was 1 DEG which was over-represented in the AKCMS11; Cca-jan_36686_c0_g1_i4 (10.05-fold up-regulated), this was in accordance with findings in soybean and sesame [56,97]. These DEGS recognized in this study might have a possible role causing CMS in this crop.…”

“…The DEG Ccajan_37653_c0_g4_i5 represents FLA11 with 9.14-fold down-regulation in CMS line with respect to the sterile line. Similar results were observed in watermelon, cotton and sesame [55,61,97].…”

“…For instance, Ccajan_47215_c0_g1_i1 was 7.14-fold downregulated and Ccajan_68741_c0_g2_i1 was 2.08-fold down-regulated. Similar findings were seen in radish, sesame and kenaf [54,97,101].…”

Elucidation of molecular mechanisms of flower form development in tree peony ( Paeonia suffriticosa ) through comparative transcriptome analysis of floral parts

“…A set of 3,7000 DEGs were identified in blueberry, among them 89% of flowering pathway genes, 86 % of MADS-box genes, and 84% of cold-regulated genes were up or down regulated in chilled flower buds compared to nonchilled flower buds [31]. A total of 1502 DEGs were detected in sterile flower buds [32]. The application of this method has yielded valuable data in tree peony.…”

Comparative transcriptome analysis indicates that a core transcriptional network mediates isonuclear alloplasmic male sterility in wheat (Triticum aestivum L.)

“…GO (http://www.geneontology.org/) and KEGG (http:// www.genome.jp/kegg/) functional annotations for the shared DEGs were obtained using BLAST2GO (http:// www.blast2go.com/) and BLASTx/BLASTp 2.2.24+, respectively. GO term and KEGG pathway enrichment analysis were performed using the shared DEGs with Goatools and KOBAS software, where the threshold was a corrected P-value ≤0.05 [54]. The relationships between the key GO terms and associated DEGs were visualized using Circos version 0.69 [55].…”