Single-Cell Transcriptome Atlas and Regulatory Dynamics in Developing Cotton Anthers.

Area of Science:

• Plant reproductive biology
• Molecular genetics
• Agricultural science

Background:

• Plant anthers contain specialized cells crucial for reproduction.
• High temperature (HT) stress induces male sterility, reducing crop yields.
• Understanding anther development and HT response at a cellular level is limited.

Purpose of the Study:

• To create the first single-cell transcriptome atlas and chromatin accessibility survey of cotton anthers.
• To map cell-specific gene expression and epigenetic landscapes during anther development.
• To investigate the impact of HT stress on anther cell function and identify key regulatory mechanisms.

Main Methods:

• Single-cell RNA sequencing (scRNA-seq) for transcriptome analysis.
• Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) for chromatin accessibility.
• Bioinformatic reconstruction of cell developmental trajectories.

Main Results:

• Detailed spatial expression atlas and epigenetic landscape of cotton anther cells.
• Identification of novel genes and precise developmental timing for meiotic, tapetal, and middle layer cells.
• Tapetal cells, vital for pollen wall synthesis, are most sensitive to HT stress.
• HT stress silences key genes (e.g., QRT3, CYP703A2) in tapetal cells by reducing chromatin accessibility, leading to abnormal pollen and male sterility.

Conclusions:

• This study provides a comprehensive resource for cotton anther development and cellular responses to heat.
• It elucidates the molecular mechanisms underlying HT-induced male sterility.
• Findings offer potential strategies for breeding heat-tolerant crops.