Fig 2: GCs dominated follicular ER stress in chicken PHFs. Morphology of follicles ((a1) A and B, (b1) A and B) after 72 h culture. Changes in the TUNEL index in SWFs ((a1) C and D, (b1) C and D) after coculture with GCs. Green: apoptotic cells. BrdU was used to label the cells ((a1) E and F, (b1) E and F) that were proliferating (red). After coculture of the D580-SYF-GCs with D280-SWFs, ER stress marker GRP78 ((a1) G and H) was increased in the GCs. After coculture of the D580-SWFs with D280-SYF-GCs, the ER marker GRP78 ((b1) G and H) was reduced in both GCs and TCs. Scale bar: 20 µm. Western blot and grey analysis of BCL2, p-PERK, ATF4, caspase12, ASK1, and GRP78 (a2) expression in D280-SWFs with D580-SYF-GCs in coculture. Western blot and grey analysis of BCL2, p-PERK, ATF4, caspase12, ASK1, and GRP78 (b2) expression in D580-SWFs with D280-SYF-GCs in coculture. By qRT-PCR analysis, CALR, PERK, GRP78, and CHOP mRNAs (a3) increased in D280-SWFs (coculture with D580-SYF-GCs). The mRNAs of CALR, PERK, GRP78, and CHOP (b3) decreased in D580-SWFs (coculture with D280-SYF-GCs). Values were the mean ± SEM of three experiments. Different lowercase letters indicated significant difference (p < 0.05).

Fig 3: Age-related ER stress in SWFs of the D280 and D580 hens. IF staining was used to observe the localization of GRP78 ((a1) A and B) and ATF4 ((a2) C and D) in SWFs of hens, and red fluorescence was used to mark GRP78 and ATF4. Scale bar: 50 µm. TEM was used to observe the ER morphology (b1) of the SWFs, and green arrows pointed to the ER. Western blot and grey analysis of caspase3, caspase12, Bax, and GRP78 (b2) expression in SWFs. Values were the mean ± SEM of three experiments. Different lowercase letters indicated significant difference (p < 0.05).