ABSTRACT
OBJECTIVE@#Our aim was to explore whether heat stress protein (HSP) 9 preferentially expresses under heat stress and affects the expression of other heat stress proteins as well as to explore the effect of HSPB9 overexpression and knockdown on apoptosis in DF-1.@*METHODS@#We used gene cloning to construct an overexpression vector of the target gene, and synthesized the target gene interference fragment to transfect the chicken fibroblast cell line. Gene and protein expression, as well as apoptosis, were detected by RT-qPCR, Western blot, and flow cytometry.@*RESULTS@#Chicken DF-1 cells showed an early state of apoptosis in the early stages of HSPB9 overexpression. In the later stages, as HSPB9 expression increased, the cells showed inhibition of apoptosis. When the cells were under heat stress, HSPB9 expression was much higher and earlier than the expression of HSPB1 and HSPA2. In addition, high expression of HSPB9 had a negative effect on HSPB1 and HSPA2 expression. This negative feedback decreased the percentage of early stages of apoptotic cells and promoted cell survival.@*CONCLUSION@#HSPB9 expression, although rapid, is detrimental to cell survival early during its overexpression. In heat stress, HSPB9 overexpression, while inhibiting the expression of HSPA2 and HSPB1, is beneficial to cell survival.