en زیست شناسی سلولی Cell Biology مقالات اصلی Original Article <div style="text-align: justify;"><strong>Background: </strong>Currently, the efficient production of chimeric mice and their survival are still challenging.&nbsp;Recent researches have indicated that preimplantation embryo culture media and manipulation lead to&nbsp;abnormal methylation of histone in the H19/Igf2 promotor region and consequently alter their gene expression&nbsp;pattern. This investigation was designed to evaluate the relationship between the methylation state of histone<br> H3 and H19/Igf2 expression in mice chimeric blastocysts.<br> <br> <strong>Methods:</strong> Mouse 129/Sv embryonic stem cells (mESCs) expressing the green fluorescent protein (mESCs-&nbsp;GFP) were injected into the perivitelline space of 2.5 days post-coitis (dpc) embryos (C57BL/6) using a micromanipulator. H3K4 and H3K9 methylation, and H19 and Igf2 expression was measured by&nbsp;immunocytochemistry and q-PCR, respectively, in blastocysts.<br> <br> <strong>Results: </strong>Histone H3 trimethylation in H3K4 and H3K9 in chimeric blastocysts was significantly less and&nbsp;greater, respectively (p< 0.05), than in controls. H19 expression was significantly less (p< 0.05), while Igf2&nbsp;expression was less, but not significantly so, in chimeric than in control blastocysts.<br> <br> <strong>Conclusions:</strong> Our results showed, that the alteration ofH3K4me3 and H3K9me3 methylation, change&nbsp;H19/Igf2 expression in chimeric blastocysts.</div> Chimeric blastocysts, H19/Igf2, Histone 3 (H3) methylation. 357 365 http://rbmb.net/browse.php?a_code=A-10-531-1&slc_lang=en&sid=1 Maryam Salimi 100319475328460017694 100319475328460017694 No Department of Biology and Anatomical Sciences, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Abolfazl Shirazi a.shirazi@ari.ir 100319475328460017695 100319475328460017695 Yes Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran & Department of Gametes and Cloning, Research Institute of Animal Embryo Technology, Shahrekord University, Shahrekord, Iran. Mohsen Norouzian* norozian93@gmail.com 100319475328460017696 100319475328460017696 No Department of Biology and Anatomical Sciences, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Ameneh Jafari 100319475328460017697 100319475328460017697 No Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Haleh Edalatkhah 100319475328460017698 100319475328460017698 No Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran. Maryam Mehravar 100319475328460017699 100319475328460017699 No Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran Mohammad Majidi 100319475328460017700 100319475328460017700 No Food and Drug Laboratory Research Center, Food and Drug Organization, MOH & ME, Tehran, Iran. Mohammad Mehdi Mehrazar 100319475328460017701 100319475328460017701 No Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.