Dynamic Expression and Chromatin Incorporation of ACT and CREM Transcription Factors in Testis Tissues of Infertile Men
Authors: Parham Jazireian, Raha Favaedi, Mohammad Ali Sadighi Gilani, Maryam Shahhoseini
Number of views: 60
Objective: Activator of CREM in the testis (ACT) is a tissue specific transcription factor which activates cAMP
responsive element modulator (CREM), a key transcription factor in differentiation of round spermatids into mature
spermatozoa. They bind to CRE region in the promoters of transition protein genes (TNP1, TNP2) and protamine genes
(PRM1 and PRM2), which are essential for sperm chromatin compaction, and regulates their transcription. This study
was conducted to consider the expression of ACT and CREM and their regulatory roles on the expression of PRM1,
PRM2, TNP1 and TNP2 genes in testis tissues of infertile men.
Materials and Methods: In this case-control study, testicular biopsies were collected from 40 infertile men and
classified into three groups: obstructive azoospermia (OA, n=10, positive control), round spermatid maturation arrest
(SMA, n=20), Sertoli cell-only syndrome (SCOS, n=10, negative control group). Using quantitative real-time polymerase chain reaction (PCR), the expression profile of ACT, CREM, TNP1, TNP2, PRM1 and PRM2 genes were assessed in
testicular samples and incorporation of ACT and CREM proteins on the promoters of PRM1, PRM2, TNP1 and TNP2
genes were also evaluated by ChIP-real time PCR.
Results: Our results demonstrated significant decrease in the expression levels of ACT, CREM and in their
incorporations on their target genes in SMA group in comparison to control groups (P≤0.05).
Conclusion: These data confirm that there is low expression and incorporation of ACT and CREM and of their target
genes in infertilities which are associated with post-meiotic arrest.