Protein phosphorylation pattern and role of products of c-erbB-1 and c-abl proto-oncogenes in murine preimplantation embryonic development

Determination of c-Abl tyrosine kinase and mTERT catalytic subunit of telomerase expression level during prenatal-postnatal mouse ovary-testis development

Expression levels of genes involved in the development of germ cells vary throughout the process from bipotential gonadal period to adult gonadal formation. In mice, developments of female and male reproductive system are regulated by germ cell-specific factors and hormones, and determinative days in this regulation are very important. c-Abl is a non-receptor tyrosine kinase with cellular functions including cell proliferation, growth and development. mTERT is involved in maintaining telomerase activity and proliferation of surviving cells. We suggested that c-Abl and mTERT might be important for the healthy development of prenatal and postnatal mouse ovary and testis. We aim to demonstrate localization and expressions of c-Abl and mTERT in crucial days of ovary and testis development in prenatal and postnatal period in mouse by immunofluorescence staining and qRT-PCR, respectively. The importance of c-Abl and mTERT expressions during the healthy gonadal development is indicated in the prenatal and postnatal gonadal development. Also, protein expression levels were detected by Western Blot in only postnatal ovary and testis. Determining the functions of the c-Abl and mTERT throughout the process will be important in terms of understanding the infertility cases in the female and male with future studies.

Interaction of the mTERT telomerase catalytic subunit with the c-Abl tyrosine kinase in mouse granulosa cells

Context: Oocyte and granulosa cells (GCs) have bidirectional communication and GCs play an important role in folliculogenesis and proliferation of GCs is very important for the development of ovulatory follicle. DNA double-strand breaks activate c-Abl protein tyrosine kinase and c-Abl has a functional role in repairement of DNA and control of telomere.Objective: In this study, we hypothesized that c-Abl has a regulative role on mTERT in mouse ovarian granulosa cells (GCs) and we aimed to detect c-Abl and mTERT interaction in mouse primary culture of GCs.Materials and methods: Mouse ovarian granulosa cell were cultured and siRNA-mediated knockdown approach was used to knockdown c-Abl expression.Results: We showed c-Abl and mTERT immunolocalization in vivo and in vitro mouse GCs. c-Abl and mTERT were constitutively expressed in mouse granulosa cells and c-Abl presented more intense expression in granulosa cells than mTERT expression. The interaction of the c-Abl-mTERT is supported by the exhibition that c-Abl siRNA knockdown cells show decreased mTERT expression. We also present an interaction between c-Abl and mTERT by immunoprecipitation. In addition, our results indicated that the down-regulation of c-Abl was also accompanied by reduced expression of proliferating cell nuclear antigen (PCNA) in GCs.Conclusions: We suggest that mTERT may associate with the c-Abl in mouse GCs and the interactions between c-Abl and mTERT suggest a role for c-Abl in the regulation of telomerase function and proliferation in mouse granulosa cells.

The Abelson tyrosine kinase (c-Abl) expression on the mouse uterus and placenta during gestational period

c-Abl is a protein tyrosine kinase which has very important roles in signal transduction, control of the cell cycle, cell motility, proliferation, and inhibition of apoptosis. We hypothesized that c-Abl may play an important role on uterine remodeling during pre-receptive, receptive and non-receptive endometrium. Our aim is to investigate the expression of c-Abl protein tyrosine kinase in uterine remodeling and placental development in mouse gestational stage. We performed c-Abl immunohistochemistry on mouse uterine tissue sections on days 1-9, 11, 13, and 15 of pregnancy. c-Abl was highly upregulated in the uterine luminal epithelium and other endometrial structures including glands and blood vessels in pre-receptive and receptive endometrium. Therefore these results demonstrate a role for c-Abl in uterine remodeling during decidualization, implantation, and placentation throughout gestation.

Analysis of gene expression in the bovine blastocyst produced in vitro using suppression-subtractive hybridization

Successful embryonic development is dependent on time and location-specific expression of appropriate genes. Unfortunately, information on stage-specific gene expression during early embryonic development in the bovine is lacking. In the present study, we compared gene expression between in vitro-produced Day 7-8 intact blastocysts (driver) and Day 9-10 hatched blastocysts (tester) using suppression-subtractive hybridization. Pools of 30 embryos for both driver and tester were used in the RNA extraction process. From limited amounts of starting material ( approximately 400 ng of total RNA), a reverse transcription-polymerase chain reaction (PCR) procedure was used to amplify the mRNA and generate sufficient cDNA to conduct suppression-subtractive hybridization. The subtracted cDNA products were cloned, and 126 cDNAs representing expressed mRNAs were isolated, sized, single-pass sequenced, and compared to known sequences in GenBank. Ninety-two clones provided sequence information for further analysis. Among these, 31 exhibited high homology to known genes. Three, 26S proteasomal ATPase (PSMC3), casein kinase 2 alpha subunit (CK2), and phosphoglycerate kinase (PGK) were selected and further characterized using real-time quantitative PCR to assess their differential expression in hatched blastocysts. Overall, a 1.3-, 1.6-, and 1.5-fold increase in expression level was observed in hatched blastocysts compared with intact blastocyst for PSMC3, CK2, and PGK, respectively. These results show that construction of subtracted cDNA libraries from small numbers of embryos is feasible and can provide information on gene expression patterns during preattachment embryogenesis.

Biology of chronic myelogenous leukemia

This article reviews the biology of chronic myelogenous leukemia (CML) and its effect on the process of hematopoiesis. The relevance of the BCR-ABL fusion protein as well as murine models are also discussed. CML has been studied more extensively than any other malignancy, yet the correlation between the clinical symptoms of chronic phase CML and the BCR-ABL oncoprotein is poorly understood. Insights from recent efforts both to develop a good in vivo animal model and to characterize the effect of the BCR-ABL oncoprotein on relevant signal molecules may lead to a better understanding of the pathophysiology of chronic phase CML and, thereby, to the development of targeted therapeutic approaches.

Thymosin alpha-1 and FA-1 monoclonal antibody affect murine preimplantation embryo development by modulating protein phosphorylation

The effects of thymosin alpha 1 (T alpha 1) and FA-1 monoclonal antibody (anti-FA-1 mAb) on murine preimplantation embryonic development were investigated by performing 2-cell embryo bioassay and by studying ova/embryos protein phosphorylation pattern (by 32P metabolic labeling and by in vitro kinase assay) and protein synthesis (by in vitro [35S]methionine labeling). T alpha 1 treatment (0.1, 0.5 and 5 ng/100 microliters) significantly increased blastulation rates (P < 0.01), blastocyst hatching rate (P < 0.0001), blastocyst diameter (P < 0.001) and number of cells per blastocyst (P < 0.0001) of the in vitro cultured 2-cell stage embryos. Anti-FA-1 mAb reduced blastulation rates (P < 0.001) primarily due to an arrest of development at morula stage. In vitro metabolic labeling of murine ova/embryos showed 32P incorporation into 4 major protein bands of murine ova (M(r) 125, 90, 68 and 31 kDa, respectively), 7 protein bands of 2-cell (M(r) 90, 68 and 31; and 145, 52, 38 and 32 kDa, respectively), 10 protein bands of morula (M(r) 150, 110, 92, 82, 70, 54, 39, 34, 30 and 29 kDa, respectively), and 15 protein bands of blastocyst (150, 110, 92, 70, 68, 54, 39, 34 and 30; and 131, 105, 52, 44, 43 and 33 kDa, respectively) stage embryos. T alpha 1 treatment (0.1-0.5 ng/100 microliters) resulted in a general increase in 32P labeling in all proteins of 2-cell, morula and blastocyst stage embryos. Anti-FA-1 mAb completely blocked 32P labeling of various proteins of murine ova, 2-cell, morula and blastocyst stage embryos, whereas control mouse myeloma IgG did not affect phosphorylation of these proteins. In vitro kinase assay performed directly on various ova/embryos extracts revealed 6 phosphoproteins (M(r) 105, 82, 55, 38, 34 and 33 kDa, respectively) that were common to ova and 2-cell embryos, besides a 43 kDa protein detected only in the ova extract. Of these phosphoproteins, T alpha 1 treatment specifically enhanced whereas anti-FA-1 mAb inhibited autophosphorylation of a 55 kDa protein of 2-cell embryos.(ABSTRACT TRUNCATED AT 250 WORDS)