Integrative Transcriptomic Analysis Reveals a Conserved Thermal-Sensitive Developmental Module in Tomato Sperm Cell Lineage

• Maryam Abdulrahman Najim

  Author

High night temperatures lower tomato (Solanum lycopersicum) yield by causing male sterility. The developing sperm cell lineage is highly sensitive to heat. Transcriptional heat responses are well characterized in vegetative tissues; however, their relationship to sperm cell development remains poorly understood. We propose that heat stress may contribute to sterility by disrupting developmental modules associated with sperm specification. We integrated two transcriptomic datasets. GSE131496 documents the response of tomato seedlings to negative temperature differentials, providing a reference set of heat-responsive genes but not a direct model of heat stress in reproductive tissues. GSE117185 contains transcriptomes from isolated sperm cell lineage stages. Using a shared Limma pipeline, we identified differentially expressed genes (adj.P < 0.05, |logFC| > 1). We then analyzed the intersection of these gene sets and profiled their correlations. A set of 359 genes showed differential expression during both temperature stress and sperm cell development. Transcriptional responses to heat and sperm cell specification correlated positively (Pearson R = 0.321, P < 0.0001). Of these genes, 73% showed concordant regulation while 27% showed discordant regulation. Their expression patterns also differed by developmental stage. A heat-sensitive transcriptional module overlaps with the sperm cell developmental program. This overlap provides candidate genes for future studies on thermotolerant tomatoes and reproductive resilience. Since the heat-response data came from seedlings, these genes still need to be tested during heat-sensitive stages of male gametophyte development.

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