Single-cell atlas maps ovarian cell changes during the pig estrus switch

The pig ovary undergoes rapid, coordinated remodeling as it shifts from proestrus into estrus, yet the cell type–specific transcriptional programs behind this transition have remained incompletely defined. A new single-nucleus RNA sequencing study published in BMC Genomics now provides a stage-resolved cellular atlas of the porcine ovary spanning proestrus and estrus, charting how individual ovarian cell populations alter their molecular states across the switch. Rather than averaging signals across whole tissue, the approach captures gene activity nucleus by nucleus, allowing researchers to distinguish the changing behavior of granulosa cells and other somatic compartments that were previously hard to separate.

The researchers generated a single-nucleus RNA sequencing atlas of porcine ovaries covering both stages and then carried out integrative analyses focused on granulosa cell heterogeneity, metabolic pathway activity, and inferred metabolic flux. The appearance of a glutamine transporter among the stage-associated features points to metabolic reprogramming as a thread running through the transition, although the study reports these as candidate molecular features identified from transcriptional data rather than as functionally validated drivers of the switch. Beyond metabolism, the team combined cell type–specific differential expression profiling with an intercellular communication network analysis across the major ovarian somatic compartments.

This systems-level comparison identified TGF-β signaling as a candidate intercellular signaling pathway associated with the transition, suggesting that the exchange of signals between ovarian cell types may be rewired as the ovary moves from proestrus into estrus. Taken together, the analyses delineate coordinated transcriptional, metabolic, and microenvironmental changes during the proestrus-to-estrus switch, offering a connected picture of how multiple cell populations and signaling routes shift in parallel rather than in isolation. The authors position the atlas as a high-resolution cellular resource for the porcine ovary across proestrus and estrus, and they propose ERBB4, SLC1A5, and TGF-β pathway components as candidate molecular features associated with estrus-related ovarian changes.

Because these candidates emerge from sequencing and computational inference, follow-up work would be needed to test whether they causally regulate the transition. Even so, the researchers suggest the findings may support improved estrus detection, earlier recognition of reproductive disorders, and more precise reproductive management in swine production systems. For now, the study's contribution is a detailed, stage-resolved map of ovarian cellular states and candidate signaling events, providing a reference framework that researchers and breeding programs can use to investigate the biology of the proestrus-to-estrus switch in pigs.

Subject of Research: Single-nucleus RNA sequencing of the porcine ovary during the proestrus-to-estrus transition

Article Title: Multicellular state transitions and signaling rewiring during the proestrus-to-estrus switch in the porcine ovary

Article References: Zhu, Z., Wang, Q., Li, M., Wu, F., Wen, T., Zhang, Y., Chen, J., Wang, J., Shen, W., & Tian, Y. (2026). Multicellular state transitions and signaling rewiring during the proestrus-to-estrus switch in the porcine ovary. BMC Genomics. https://doi.org/10.1186/s12864-026-13491-3

Image Credits: AI Generated

DOI: 10.1186/s12864-026-13491-3

Keywords: Multicellular, state, transitions, signaling, rewiring, during, proestrus-to-estrus, switch, porcine, ovary, scientific research