Immunolocalization of the High-Mobility Group N2 protein and acetylated histone H3K14 in early developing parthenogenetic bovine embryos derived from oocytes of high and low developmental competence

• Published in: Molecular reproduction and development 2008-02, Vol.75 (2), p.282-290
• Main Authors: Bastos, Guilherme M., Gonçalves, Paulo Bayard D., Bordignon, Vilceu
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; bovine; Cattle; embryo development; Embryo, Mammalian - physiology; Embryology: invertebrates and vertebrates. Teratology; Embryonic Development - physiology; Female; follicle size; Fundamental and applied biological sciences. Psychology; General aspects; General aspects. Development. Fetal membranes; H3K14ac; Histones - metabolism; HMGN2; HMGN2 Protein - metabolism; Kinetics; Oocytes - physiology; Organ Culture Techniques; Ovarian Follicle - cytology; Ovarian Follicle - physiology; Parthenogenesis; Zygote - physiology
• ISSN: 1040-452X; 1098-2795
• DOI: 10.1002/mrd.20798

This study investigated differences in the distribution of acetylated histone H3 at Lysine 14 (H3K14ac) and the High‐Mobility Group N2 (HMGN2) protein in the chromatin of early‐ (before 24 hr) and late‐cleaved (after 24 hr) bovine embryos derived from small‐ (1–2 mm) and large‐follicles (4–8 mm). The presence of HMGN2 and H3K14ac has been associated with different nuclear functions including chromatin condensation, transcription, DNA replication and repair. In vitro matured oocytes were parthenogenetically activated (PA) and cultured in synthetic oviduct fluid medium. Early‐ and late‐cleaved embryos were fixed at 36, 50, 60, 70 and 80 hr after PA to detect the presence of H3K14ac and HMGN2. The rates of nuclear maturation (81.1% vs. 58.7%), early cleavage (46.9% vs. 38.9%), and development to blastocyst stage (34.3% vs. 18.9%) were higher (P