Thymosins β-4 and β-10 are expressed in bovine ovarian follicles and upregulated in cumulus cells during meiotic maturation.
β-Thymosins are small proteins that regulate the actin cytoskeleton and are involved in cell motility, differentiation, the induction of metalloproteinases, in anti-inflammatory processes and tumourigenesis. However, their roles in the ovary have not yet been elucidated. Using transcriptomics and real time reverse transcription-polymerase chain reaction validation, the present study demonstrates that thymosin β-4 (TMSB4) and thymosin β-10 (TMSB10) are upregulated in bovine cumulus cells (CCs) during in vitro maturation of cumulus-oocyte complexes (COCs) in parallel with an increase in mRNA expression of HAS2, COX2 and PGR genes. Using immunocytochemistry, both proteins were found to be localised mainly in granulosa cells, CCs and oocytes, in both the cytoplasm and nucleus, as well as being colocalised with F-actin stress fibres in CCs. Using different maturation mediums, we showed that the expression of TMSB10, but not TMSB4, was positively correlated with COC expansion and progesterone secretion and negatively correlated with apoptosis. Immunofluorescence, coupled with terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL), demonstrated the absence of TMSB4 and/or TMSB10 in apoptotic cells. TMSB10 expression was higher in COCs matured in vivo than in vitro, and differences related to the age of the animal were observed. TMSB4 and/or TMSB10 expression was unchanged, whereas HAS2 overexpressed in CCs from oocytes that developed to the blastocyst stage in vitro compared with those that did not. Thus, TMSB4 and/or TMSB10 ovarian expression patterns suggest that these two thymosins may be involved in cumulus modifications during maturation.
Salhab
Mohamad
M
INRA, UMR85 Physiologie de la Reproduction et des Comportements, CNRS,UMR6175, Université de Tours, Nouzilly, France.
Papillier
Pascal
P
Perreau
Christine
C
Guyader-Joly
Catherine
C
Dupont
Joelle
J
Mermillod
Pascal
P
Uzbekova
Svetlana
S
D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D002417:Cattle; D003470:Culture Media / Q000378:metabolism; D054885:Cumulus Cells / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000235:genetics; D046149:Embryo Culture Techniques / Q000662:veterinary; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary; D005455:Fluorescent Antibody Technique; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental; D014453:Glucuronosyltransferase / Q000235:genetics; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D008540:Meiosis; D020411:Oligonucleotide Array Sequence Analysis; D009866:Oogenesis; D006080:Ovarian Follicle / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011980:Receptors, Progesterone / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013947:Thymosin / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D015854:Up-Regulation; D000099201:Thymosin beta(4)
D003470:Culture Media; D051546:Cyclooxygenase 2; D014453:Glucuronosyltransferase; D011374:Progesterone; D012333:RNA, Messenger; D011980:Receptors, Progesterone; D013947:Thymosin; D000099201:Thymosin beta(4); C039302:thymosin beta(10)