Abstract
ZNF33B belongs to recently duplicated Krüppel-associated box domain zinc finger proteins (KRAB-ZFPs), which is widely present in various organs, and some evidence showed that its expression is altered in the ovary undergoing superovulation. In this study, the expression of ZNF33B in ovary and early embryo was determined by immunohistochemistry and immunofluorescence techniques. Results showed that the expression of ZNF33B in the ovary was mainly in the cytoplasm of oocytes and granulosa luteal cells of ovarian corpus luteum and significantly reduced during follicular ovulation to luteal degeneration. The expression of ZNF33B in the early embryo transferred from the nucleus to the whole cell, suggesting that the expression of ZNF33B is spatiotemporally specific. Then, in combination with the single nucleotide polymorphism (SNP) database, the g.-61GT mutant of the 5-untranslated region (5 UTR) of the ZNF33B gene was screened out from 556 Changbaishan black cattle, and the frequency of the mutant gene was counted. The statistics of superovulation and superovulation traits confirmed significant differences between the two genotypes in the quantity and quality of oocytes obtained after superovulation. This study confirmed, for the first time, the effect of ZNF33B gene polymorphism on superovulation traits and suggested that the mutation could provide a basis for cattle breeding and improving animal fertility.
Highlights
Zinc finger proteins were first found in Xenopus oocytes, which are widely distributed in organisms (Krishna et al, 2003)
The transcriptomic data of bovine embryonic developmental stages (GSE143848) showed that ZNF33B was consistently poorly expressed at the oocyte and 2–16 cell stages, but the expression was gradually upregulated
For comparison of the differences in the expression levels between ZNF33B in bovine at the cortical part of the ovary in the luteal-phase ovary, the cortical part of the ovary in the follicular phase ovary, and the medullary part of the ovary, the ZNF33B protein in these three tissues were detected by Western blot
Summary
Zinc finger proteins were first found in Xenopus oocytes, which are widely distributed in organisms (Krishna et al, 2003). 1 % of the sequences in human genome encodes proteins with zinc finger structure. The protein size and amino acid sequence of KRAB box structure and zinc finger binding domain at the C terminal differed among different subtypes (Iuchi et al, 2001; Yang et al, 2017). During the early stages of embryogenesis, KRAB-type zinc finger proteins could induce specific silencing of endogenous reverse transcription elements by mediating histone methylation, histone deacetylation, and DNA methylation, resulting in changes in chromosomal epigenetic modifications. In this manner, genomic stability and normal embryonic development could be maintained (Rowe et al, 2011).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
