Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2/B1) is an N6-methyladenosine (m6A) RNA modification regulator and a key determinant of premRNA processing, mRNA metabolism and transportation in cells. Currently, m6A reader proteins such as hnRNPA2/B1 and YTHDF2 has functional roles in mice embryo. However, the role of hnRNPA2/B1 in porcine embryogenic development are unclear. Here, we investigated the developmental competence and mRNA expression levels in porcine parthenogenetic embryos after hnRNPA2/B1 knock-down. HhnRNPA2/B1 was localized in the nucleus during subsequent embryonic development since zygote stage. After hnRNPA2/B1 knock-down using double stranded RNA injection, blastocyst formation rate decreased than that in the control group. Moreover, hnRNPA2/B1 knock-down embryos show developmental delay after compaction. In blastocyste stage, total cell number was decreased. Interestingly, gene expression patterns revealed that transcription of Pou5f1, Sox2, TRFP2C, Cdx2 and PARD6B decreased without changing the junction protein, ZO1, OCLN, and CDH1. Thus, hnRNPA2/B1 is necessary for porcine early embryo development by regulating gene expression through epigenetic RNA modification.
Interferon tau (IFNT) regulation, an anti-luteolytic factor produced by conceptuses of the ruminant ungulates, is essential for the maintenance of early pregnancy, but a definitive mechanism for its temporal transcription has not been elucidated. We and others have observed the T-box protein eomesodermin (EOMES) exhibited high mRNA expression in the ovine embryonic trophectoderm; thus, both caudal-relatedhomeobox-2 (CDX2) and EOMES coexist during the early stages of conceptus development. Objective of this study was to examine the effect of EOMES on ovine IFNT gene transcription when evaluated with CDX2, ETS2 and AP1 transcription factors implicated in the control of cell differentiation in the trophectoderm. In this study, quantitatively via reverse transcription-polymerase chain reaction (RT-PCR) analysis between ovine trophoblast cells was initially performed, finding that transcription factors CDX2 and ‘EOMES transcription factor mRNAs’ were specific to trophectoderm cells. These mRNAs were also found in days 15, 17, and 21 ovine conceptuses. Furthermore, human choriocarcinoma JEG3 cells (trophoblast cell line) were cotransfected with an ovine IFNT (-654bp)-luciferase reporter (-654-oIFNT-Luc) construct and several transcription factor expression plasmids. Cotransfection of the reporter construct with CDX2, ETS2 and AP1 increased transcription of -654-oIFNT-Luc by about 11-fold compared with transfection of the construct alone. When cells were initially transfected with EOMES followed by transfection with CDX2, ETS2 and/or AP1, the expression of -654-oIFNT-Luc was decreased. Also, EOMES factor inhibited the stimulatory activity of CDX2 alone. These results suggest that when conceptuses attach to the uterine epithelium, ovine IFNT gene transcription is down-regulated by an increase of EOMES factor expression in the attached ovine trophoblast cells.
인류의 21세기를 바이오테크놀로지(Biotechnology) 의 시대라고 정의할 수 있을 만큼 오늘날 해당 영 역에서 큰 성과를 거두었고 현재에도 나날이 발전 하고 있다. 그중에서도 가장 핵심적인 기술은 인체유전자기술이다. 동시에 인체유전자기술은 인류사회에 긍정적인 전망을 보여주었기에 21세기 생명공학의 Green gold라 불리기도 한다. 인체유 전자기술이라는 새로운 고도첨단기술에 대하여 우리 사회는 어떠한 시각으로 바라보고 어떠한 태도를 취하여야 하며 어떠한 법률규제를 통하여 사회의 질서를 유지하고 윤리도덕을 지킬 것인지는 21세기 바이오테크놀로지시대의 현안과 과제라 할 수 있다.
중국은 20세기 90년대부터 유전자과학기술의 법률규제 건설을 시작하였다. 외국의 입법 시기와 비교해 보았을 때 입법이 늦지는 않다. 하지만 현행 유전자과학기술 법체계를 보았을 때 많은 문제가 존재하는데, 입법이 기술의 발전을 따라가지 못 하고, 인체유전자과학기술에 있어서는 더욱 많은 법적 盲點을 보는 점이다. 또한 이것이 원인이 되어 기술 연구에 보다 느슨한 규제가 적용되었다. 독일은 1990년에 세계최초로 “유전자기술법”을 제정하였다. 중국과 비슷한 시기의 입법이기는 하나, 해당 법규는 단행법규의 형식으로 상당히 구체적으로 유전자과학기술연구에서 준수하여야 할 법률사항을 규정하고 있다. 호주의 「유전자기술법 2000」은 2000년 12월 21일에 총독의 정식서명에 의하여 2001년 6월 20일에 발효하였으며, 또 한 법률규제를 통한 사회질서의 유지 외에도 전문적으로 “유전자기술 관리 사무소”라는 기구를 설 립함으로써 국민의 기본권과 환경보호 등의 문제를 감독, 관리하고 있다. 독일과 호주 외에도 많은 국가들이 유전자과학 기술발전의 잠재적 위험성을 인식하고 이에 대응되는 법률규제를 두고 있다.
Variance of conceptus interferon tau (IFNT), produced by the embryonic trophectoderm, is known as a major conceptus protein that signals the process of maternal recognition of pregnancy in ruminants, essential for the maintenance of early pregnancy. Similar to other IFN genes such as IFNA and IFNB, multiple IFNT genes are present. However, some kinds of IFNT genes actively transcribed and regulated in bovine conceptuses have not been well characterized. In this study, during the course of bovine IFNT gene transcription through the use of next generation sequencer SOLiD3, revealed that among 38 IFN genes registered, only two transcripts, IFNT1 and IFNTc1, were found in conceptuses during early pregnancy. Also, to identify a transcription factor(s) involved in the regulation of IFNT genes, mRNAs for various known transcription factors were investigated by real-time PCR in conceptus tissues, respectively. Furthermore, compared to the IFNT genes, IFNT1 and IFNTc1 had same active levels, which were previously shown to correlate with the appearance of effective antiviral activity. However, the expression levels of these Luc activities differed. Bovine ear fibroblast (EF) cells were cotransfected with luciferase reporter constructs carrying upstream (–631 to -51) promoter regions of IFNT1 or IFNTc1 and various transcription factor expression plasmids, CDX2, AP1(JUN), ETS2 and/or cAMP-response element binding protein (CREB)-binding protein (CREBBP). CDX2, either alone with the other 2 transcription factors, was found to increase luciferase activity approximately 14- and 11-folds, respectively. The degree of transcriptional activation of the IFNTc1 gene was not similar to that IFNT1 gene by AP1, ETS2 or/and CREBBP, expression plasmid. These results suggest that two isoforms of bovine conceptus IFNT genes are regulated differently in conceptuses during early pregnancy.
Cotton aphid infests more than 700 plants and a major pest of various horticultural crops worldwide. The glucose regulated protein 78 (GRP78) is a member of heat shock protein 70. Its expression is associated with the nutritional changes as well as environmental stresses. The full sequences of grp78 cDNA of Aphis gossypii was determined. It had conserved motifs of hsp genes and terminated in KDEL which is common to GRP78. Quantitative realtime PCR showed that its level was changed during development and also upregulated by starvation. However, its level was not much changed by heat stress. The level of grp78 can be use to understand nutritional physiology on insects.
Several Mites are currently the most serious threat to the world bee industry. The ectoparasitic honey bee mites was originally confined to the Asian honey bee(Apis cerana etc.). Varroa destructor and Tropilaelaps clareae has plagued European honey bees, Apis mellifera. Differences in mite tolerance are reported between two honey bee species A. mellifera and A. cerana. We were amplified antimicrobial peptide cDNA genes (Defencin, Abaecin, Royalisin, Apidaecin and Hymenoptaecin) by RT-PCR. We explored the transcriptional response to mite parasitism in A. mellifera 4th instars larvae which differ in susceptibility to V. destructor and T. clareae, comparing parasitized and non-parasitized 4th instars larvae (worker and Drone) from same hive. Differential gene expression of worker bees and Drone bees induced by mites (V. destructor and T. clareae) infection was investigated by northern blot. Mites (V. destructor and T. clareae) parasitism caused changes in the expression of genes related to sex distinction. Bees tolerant to mites (V. destructor and T. clareae) were mainly characterized by differences in the expression of genes regulating antimicrobial gene expression. It provides a first step toward better understanding molecular expression involved in this differential sex distinction host-parasite relationship. We were detected bee virus in A. mellifera, comparing parasitized and non-parasitized 4th instars larvae (worker and Drone). Therefore, this result was demonstrated that mites were another possible route of horizontal transmission, as several viruses were detected in mites and their hosts.
The present study assessed the effect of FSH and LH on oocyte meiotic, cytoplasmic maturation and on the expression level and polyadenylation status of several maternal genes. Cumulus-oocyte complexes were cultured in the presence of FSH, LH, or the combination of FSH and LH. Significant cumulus expansion and nuclear maturation was observed upon exposure to FSH alone and to the combination of FSH and LH. The combination of FSH and LH during entire IVM increased the mRNA level of four maternal genes, C-mos, Cyclin B1, Gdf9 and Bmp15, at 28 h. Supplemented with FSH or LH significantly enhanced the polyadenylation of Gdf9 and Bmp15; and altered the expression level of Gdf9 and Bmp15. Following parthenogenesis, the exposure of oocytes to combination of FSH and LH during IVM significantly increased cleavage rate, blastocyst formation rate and total cell number, and decreased apoptosis. In addition, FSH and LH down-regulated the autophagy gene Atg6 and upregulated the apoptosis gene Bcl-xL at the mRNA level in blastocysts. These data suggest that the FSH and LH enhance meiotic and cytoplasmic maturation, possibly through the regulation of maternal gene expression and polyadenylation. Overall, we show here that FSH and LH inhibit apoptosis and autophagy and improve parthenogenetic embryo competence and development.
S-adenosylhomocysteine hydrolase-like protein 1 (AHCYL1), also known as IP3 receptor- binding protein released with IP3 (IRBIT), is a member of the AHCY-like protein family. AHCYL1 protein regulates IP3-induced Ca2+ release in the cytoplasm of cells and, therefore, is likely to be an important gene regulating various biological processes in the oviduct of chickens. Inmammals, expression is greatest during activation of dendritic cells which are antigen presenting cells associated with immunoregulatory processes in blood and skin. However, the identification of the AHCYL1 gene in chickens has not been investigated. In the present study, we first used RT-PCR to demonstrate AHCYL1 gene expression in adult chicken organs and oviducts of immature chickens treated with DES (diethylstilbesterol, a synthetic estrogen agonist). The results indicated that AHCYL1 mRNA is expressed in chicken reproductive organs (testis, ovary and oviduct). Inaddition, expression of AHCYL1 mRNA increased in response to DES-treated immature oviducts compared to the non-treated control immature oviducts of chickens. Interestingly, AHCYL1 was abundant in the cytoplasm of luminal and glandular epithelia, but not in other cell-types such as stroma and connective tissues, of the chicken oviduct. These results suggest that AHCYL1 is a novel estrogen-stimulated gene associated with development of the chicken oviduct, as well as functions of oviductal glandular and luminal epithelia that may include activation of resident immune cells, such as dendritic cells.
Recent studies on nuclear transfer and induced pluripotent stem cells have demonstrated that differentiated somatic cells can be returned to the undifferentiated state by reversing their developmental process. These epigenetically reprogrammed somatic cells may again be differentiated into various cell types, and used for cell replacement therapies through autologous transplantation to treat many degenerative diseases. To date, however, reprogramming of somatic cells into undifferentiated cells has been extremely inefficient. Hence, reliable markers to identify the event of reprogramming would assist effective selection of reprogrammed cells. In this study, a transgene construct encoding enhanced green fluorescent protein (EGFP) under the regulation of human Oct4 promoter was developed as a reporter for the reprogramming of somatic cells. Microinjection of the transgene construct into pronuclei of fertilized mouse eggs resulted in the emission of green fluorescence, suggesting that the undifferentiated cytoplasmic environment provided by fertilized eggs induces the expression of EGFP. Next, the transgene construct was introduced into human embryonic fibroblasts, and the nuclei from these cells were transferred into enucleated porcine oocytes. Along with their in vitro development, nuclear transfer embryos emitted green fluorescence, suggesting the reprogramming of donor nuclei in nuclear transfer embryos. The results of the present study demonstrate that expression of the transgene under the regulation of human Oct4 promoter coincides with epigenetic reprogramming, and may be used as a convenient marker that non-invasively reflects reprogramming of somatic cells.
본 연구에서는 외래 유전자의 지속적인 발현에 의한 형질 전환 개체나 세포의 생리적인 부작용을 최소화하기 위하여 hTPO 유전자의 발현을 조절할 수 있는 tetracycline-inducible retrovirus vector system을 구축하고자 하였다. hTPO 유전자는 사람의 간암세포인 HepG2에서 분리한 RNA를 주형으로 하여 RT-PCR 방법을 이용하여 확보하였으며, 이 유전자를 MLV 유래의 vector에 도입하여 pLNChTPOW를 재조합하였다. 재조합한 vector는 GP2 293 포장세포에 도입하여 바이러스를 생산하였으며, 이 바이러스를 이용하여 감염시킨 여러 표적세포에서 hTPO의 발현을 확인하였다. 또한, hTPO의 발현을 유도적으로 조절할 수 있도록 하기 위하여 hTPO를 one vector 형태의 Tet-On vector system에 도입하였으며, 발현의 유도 조건에서 보다 강한 발현을 위하여 WPRE 서열을 여러 위치에 도입하였다. 구축한 Tet system의 발현 조절 정도는 각 바이러스를 감염시켜서 구축한 CEF와 PFF 세포에서 RT-PCR과 Western blot, 그리고 ELISA 방법을 이용하여 확인하였다. 그 결과, CEF에서는 WPRE 서열이 hTPO 유전자의 3'에 위치한 경우에서, PFF에서는 WPRE가 rtTA의 3'에 위치한 경우의 vector system에서 가장 높은 발현율과 유도율을 나타내었다. 이는 Tet system에서의 hTPO 유전자 발현 조절이 매우 효율적으로 이루어지며, 세포주에 따른 의존적인 조절 양상을 보이는 것을 의미한다. 따라서 hTPO의 대량 생산을 위한 생체 반응기로서의 형질 전환 동물의 개발을 보다 효율적으로 수행하려면 적절한 Tet system이 선별적으로 적용되어야 할 것이다.