Reproductive phasiRNAs and miRNA networks respond differentially to heat stress during early maize pollen development
This study investigates the molecular responses of early developing maize pollen to short-term heat stress using integrated mRNA-seq and small RNA-seq profiling. Two maize inbred lines with contrasting heat responses, the heat-sensitive temperate line A188 and the heat-tolerant tropical line CML228, were subjected to a 48-h moderate heat treatment at the pollen mother cell to early meiocyte stage under 35°C/25°C day/night conditions. Meiocytes, tetrads, and unicellular microspores were collected from control and heat-stressed plants, with three biological replicates per genotype, stage, and treatment, generating 36 small RNA-seq libraries and 36 3' mRNA-seq libraries. Small RNA sequencing was used to characterize miRNA and reproductive phasiRNA dynamics, whereas mRNA-seq was used to profile heat-responsive transcriptomic changes. The dataset captures genotype- and stage-dependent responses, including stable global phasiRNA abundance, dynamic miRNA expression changes, and delayed transcriptomic responses that peak at the microspore stage. These data provide a stage-resolved molecular resource for studying pollen thermotolerance mechanisms in maize and other cereal crops.
This study investigates the molecular responses of early developing maize pollen to short-term heat stress using integrated mRNA-seq and small RNA-seq profiling. Two maize inbred lines with contrasting heat responses, the heat-sensitive temperate line A188 and the heat-tolerant tropical line CML228, were subjected to a 48-h moderate heat treatment at the pollen mother cell to early meiocyte stage under 35°C/25°C day/night conditions. Meiocytes, tetrads, and unicellular microspores were collected from control and heat-stressed plants, with three biological replicates per genotype, stage, and treatment, generating 36 small RNA-seq libraries and 36 3' mRNA-seq libraries. Small RNA sequencing was used to characterize miRNA and reproductive phasiRNA dynamics, whereas mRNA-seq was used to profile heat-responsive transcriptomic changes. The dataset captures genotype- and stage-dependent responses, including stable global phasiRNA abundance, dynamic miRNA expression changes, and delayed transcriptomic responses that peak at the microspore stage. These data provide a stage-resolved molecular resource for studying pollen thermotolerance mechanisms in maize and other cereal crops.