biostudies-literatureChen LYan WuYan WU1630https://www.ebi.ac.uk/biostudies/studies/S-EPMC12562530biostudies-literatureUnknown14(20)In poultry production, the laying rate is a critical economic trait, as high egg production significantly enhances profitability. Mitogen-activated protein kinase-activated protein kinase 3 (<i>MK3</i>) is a member of the mitogen-activated protein kinase (MAPK) family, which plays an important role in follicular development. Our previous RNA-seq analysis revealed that <i>MK3</i> expression was significantly altered in the ovaries of laying hens exposed to normal versus light-deprivation conditions. Based on previous RNA-seq analysis of chicken ovaries, this study focused on the <i>MK3</i> gene to explore its role in regulating apoptosis of follicular granulosa cells in laying hens. The results demonstrated that <i>MK3</i> overexpression induced granulosa cell apoptosis by modulating the exCells&lt;i&gt;MK3&lt;/i&gt; Gene Upregulates Granulosa Cell Apoptosis Through the TNF/P38 MAPK Pathway in Chicken.PMC12562530China Agriculture Research System of MOF and MARA (CARS-40, CARS-41)National Key Research and Development Program of China (2022YFD1300100)National Natural Science Foundation of China (32202665)Supports High Quality Development of Seed Industry Fund Project of Hubei Province (HBZY2023B007),Liu JZhang YPi JChen LWu Yfalse&lt;i&gt;MK3&lt;/i&gt; Gene Upregulates Granulosa Cell Apoptosis Through the TNF/P38 MAPK Pathway in Chicken.In poultry production, the laying rate is a critical economic trait, as high egg production significantly enhances profitability. Mitogen-activated protein kinase-activated protein kinase 3 (<i>MK3</i>) is a member of the mitogen-activated protein kinase (MAPK) family, which plays an important role in follicular development. Our previous RNA-seq analysis revealed that <i>MK3</i> expression was significantly altered in the ovaries of laying hens exposed to normal versus light-deprivation conditions. Based on previous RNA-seq analysis of chicken ovaries, this study focused on the <i>MK3</i> gene to explore its role in regulating apoptosis of follicular granulosa cells in laying hens. The results demonstrated that <i>MK3</i> overexpression induced granulosa cell apoptosis by modulating the ex2025-01-01T00:00:00Z2025 Oct2026-05-14T03:21:03.883Z2026-05-14T03:12:48.185ZS-EPMC125625304114884510.3390/cells14201630