Porcine nuclear transfer using somatic donor cells altered to express male germ cell function

2009 ◽  
Vol 21 (7) ◽  
pp. 882 ◽  
Author(s):  
Sangho Roh ◽  
Hye-Yeon Choi ◽  
Sang Kyu Park ◽  
Cheolhee Won ◽  
Bong-Woo Kim ◽  
...  

Recent studies reported that the direct transformation of one differentiated somatic cell type into another is possible. In the present study, we were able to modulate the cell fate of somatic cells to take on male germ cell function by introducing cell extracts derived from porcine testis tissue. Fibroblasts were treated with streptolysin O, which reversibly permeabilises the plasma membrane, and incubated with testis extracts. Our results showed that the testis extracts (TE) could activate expression of male germ cell-specific genes, implying that TE can provide regulatory components required for altering the cell fate of fibroblasts. Male germ cell function was sustained for more than 10 days after the introduction of TE. In addition, a single TE-treated cell was injected directly into the cytoplasm of in vitro-matured porcine oocytes. The rate of blastocyst formation was significantly higher in the TE-treated nuclear donor cell group than in the control cell group. The expression level of Nanog, Sox9 and Eomes was drastically increased when altered cells were used as donor nuclei. Our results suggest that TE can be used to alter the cell fate of fibroblasts to express male germ cell function and improve the developmental efficiency of the nuclear transfer porcine embryos.

2007 ◽  
Vol 19 (1) ◽  
pp. 189
Author(s):  
H.-Y. Choi ◽  
C. Won ◽  
B.-W. Kim ◽  
Y.-J. Kang ◽  
G.-H. Kang ◽  
...  

Somatic cell cloning has promise for medical treatment using embryonic stem cells derived from cloned embryos. However, porcine cloning by somatic cell nuclear transfer has been inefficient and, even after birth, cloned pigs are found to carry a variety of abnormalities. Moreover, recent molecular analyses of cloned embryos have revealed abnormal epigenetic modifications. Therefore, the prevention of epigenetic errors is expected to lead to the improvement of the success rate in animal cloning. Reports of recent studies indicate that the direct transformation of one differentiated somatic cell type into another is possible and would be advantageous for producing isogenic replacement cells. Therefore, in this study, we modulated the cell fate of somatic donor cells by introducing cell extracts derived from porcine testis. Several porcine somatic cells, including primary and stabilized porcine fibroblasts or epithelial kidney cells, were treated with streptolysin O (SLO; 230 ng mL-1), which reversibly permeablizes plasma membrane, and incubated for 30 min with testis cell-derived cell extracts (4 mg mL-1). To reseal plasma membranes, cells were placed in DMEM containing 30% FBS and 2 mM CaCl2 for 30 min. After resealing the cell membranes, we incubated the cells for 3 weeks and analyzed the expression of testis-specific genes such as protamine 1, protamine 2, SOX 9, mullerian inhibitory substance (MIS), preproacrosine (ACR), phosphoglycerate kinase 2 (PGK-2), protein C, and c-kit ligand. In the reprogrammed primary porcine fibroblasts or epithelial kidney cells, the porcine testis extracts were able to activate the expression of the porcine testis sertoli cell-specific genes. The male germ cell functions were sustained for more than 10 days after the reprogramming process. Then, in vitro-matured oocytes were enucleated and a single cell (either reprogrammed or intact) was injected directly into cytoplasm of the oocytes. The reconstructed embryos were activated electrically and cultured in vitro for 7 days. The rate of blastocyst formation was significantly higher (P < 0.05; chi-square test) in the reprogrammed nuclear donor cells (27/119; 22.7 � 5.0%) than in the control (intact) cells (11/83; 13.3 � 3.2%). Taken together, our results suggest that testis-derived cell extracts can be successfully used to reprogram fibroblasts to express male germ cell function, thus improving the developmental efficiency of the nuclear transfer embryos.


2008 ◽  
Vol 78 (Suppl_1) ◽  
pp. 304-304
Author(s):  
Sangho Roh ◽  
Hye-Yeon Choi ◽  
SangKyu Park ◽  
Cheolhee Won ◽  
Ssang-Goo Cho

2006 ◽  
Vol 18 (2) ◽  
pp. 229
Author(s):  
H.-Y. Choi ◽  
B.-W. Kim ◽  
E.-R. Lee ◽  
S. Roh ◽  
S.-G. Cho

The concept of epigenetic reprogramming of a somatic nucleus was supported by the birth of cloned animals and the derivation of embryonic stem cells after nuclear transplantation into oocytes. Moreover, recent studies reported that the direct transformation of one differentiated somatic cell type into another is possible and would be advantageous for producing isogenic replacement cells. In this study, we were able to modulate the cell fate of fibroblasts by introducing cell extracts derived from a mast cell line, RBL-2H3. NIH-3T3 cells were treated with streptolysin O (SLO; 230 ng/mL), which reversibly permeablizes plasma membrane, and incubated for 30 min with the mast cell- derived cell extracts (4 mg/mL). After resealing the membrane of the cells, we incubated the cells for 3 weeks and then analyzed them for the expression of mast cell-specific genes such as MAFA (mast cell function-associated antigen) and FceRI (high-affinity IgE receptor). Our results showed that the cell extracts can activate the expression of mast cell-specific genes, implying that cell extracts can provide regulatory components required for reprogramming the cell fate to initiate a transcriptional program specific for the cell type. Moreover, mast cell-specific degranulation and cell morphology changes were observed in cultured mouse fibroblasts. We could detect mast cell-specific functions even after 15 days of incubation. Next, to induce porcine fibroblasts to take on testis sertoli cell-specific properties, we reversibly permeablized porcine primary fibroblasts with SLO (230 ng/mL) and incubated the cells with porcine testis extracts (4 mg/mL). As expected, in the reprogrammed primary porcine fibroblasts, the porcine testis extracts activated the expression of porcine testis sertoli cell-specific genes including protamine 1 and 2, SOX9, MIS (mullerian inhibitory substance), preproacrosine (ACR), phosphoglycerate kinase-2 (PGK-2), protein C, and c-kit ligand. The male germ cell functions were sustained for more than 10 days after the reprogramming process. Taken together, our data suggest that testis- or mast cell-derived cell extracts can reprogram fibroblasts to express male germ cell or mast cell functions, respectively, supporting the concept that cell extracts can reprogram the genome activity to activate cell-specific gene expression. This work was supported by ARPC (Grant no. 204117-03-1-HD110) in Korea, and by Biogreen 21 program (Grant no. 20050401034658).


FEBS Letters ◽  
2012 ◽  
Vol 586 (10) ◽  
pp. 1497-1503 ◽  
Author(s):  
Xiaowen Cheng ◽  
Junbo Liang ◽  
Yu Teng ◽  
Jun Fu ◽  
Shiying Miao ◽  
...  

Author(s):  
Emma Carley ◽  
Rachel K. Stewart ◽  
Abigail Zieman ◽  
Iman Jalilian ◽  
Diane. E. King ◽  
...  

AbstractWhile the mechanisms by which chemical signals control cell fate have been well studied, how mechanical inputs impact cell fate decisions are not well understood. Here, using the well-defined system of keratinocyte differentiation in the skin, we examine whether and how direct force transmission to the nucleus regulates epidermal cell fate. Using a molecular biosensor, we find that tension on the nucleus through Linker of Nucleoskeleton and Cytoskeleton (LINC) complexes requires integrin engagement in undifferentiated epidermal stem cells, and is released during differentiation concomitant with decreased tension on A-type lamins. LINC complex ablation in mice reveals that LINC complexes are required to repress epidermal differentiation in vivo and in vitro and influence accessibility of epidermal differentiation genes, suggesting that force transduction from engaged integrins to the nucleus plays a role in maintaining keratinocyte progenitors. This work reveals a direct mechanotransduction pathway capable of relaying adhesion-specific signals to regulate cell fate.


2018 ◽  
Author(s):  
Kathryn E. Kistler ◽  
Tatjana Trcek ◽  
Thomas R. Hurd ◽  
Ruoyu Chen ◽  
Feng-Xia Liang ◽  
...  

ABSTRACTGerm granules are non-membranous ribonucleoprotein granules deemed the hubs for post-transcriptional gene regulation and functionally linked to germ cell fate across species. Little is known about the physical properties of germ granules and how these relate to germ cell function. Here we study two types of germ granules in the Drosophila embryo: cytoplasmic germ granules that instruct primordial germ cells (PGCs) formation and nuclear germ granules within early PGCs with unknown function. We show that cytoplasmic and nuclear germ granules are phase transitioned condensates nucleated by Oskar protein that display liquid as well as hydrogel-like properties. Focusing on nuclear granules, we find that Oskar drives their formation in heterologous cell systems. Multiple, independent Oskar protein domains synergize to promote granule phase separation. Deletion of Oskar’s nuclear localization sequence specifically ablates nuclear granules in cell systems. In the embryo, nuclear germ granules promote germ cell divisions thereby increasing PGC number for the next generation.


2007 ◽  
Vol 19 (1) ◽  
pp. 142
Author(s):  
K. Inoue ◽  
N. Ogonuki ◽  
H. Miki ◽  
S. Noda ◽  
S. Inoue ◽  
...  

Although cloning animals by somatic cell nuclear transfer is generally an inefficient process, use of appropriate donor cell types may improve the cloning outcome significantly. Among the donor cells tested so far, mouse embryonic stem cells have given the best efficiency in terms of the development of reconstructed embryos into offspring. In this study, we examined whether 2 in vitro-produced pluripotent stem cells—neural stem cells (NSCs) and mesenchymal stem cells (MSCs)—could be better nuclear donors than other differentiated cells. Embryos were reconstructed by transfer of nuclei from NSCs or MSCs with full potential for differentiation in vitro. Most (76%) of the 2-cell NCS embryos developed to the 4-cell stage; 43% implanted and 1.6% developed to term after transfer to pseudopregnant recipients. These rates were very similar to those of embryos cloned from fibroblast cell nuclei. Interestingly, in the patterns of zygotic gene expression, NSC embryos were more similar to in vitro-fertilized embryos than fibroblast cloned embryos. By contrast, embryos reconstructed using MSC nuclei showed lower developmental ability and no implantation was obtained after embryo transfer. Chromosomal analysis of the donor MSCs revealed very high frequencies of monosomy and trisomy, which might have caused the very poor post-implantation development of embryos following nuclear transfer. Thus, in vitro-produced pluripotent cells can serve as donors of nuclei for cloning mice, but may be prone to chromosomal aberrations leading to a high rate of cloned embryo death.


2011 ◽  
Vol 23 (1) ◽  
pp. 128
Author(s):  
J. Lee ◽  
J. Park ◽  
Y. Chun ◽  
W. Lee ◽  
K. Song

Study for equine somatic cell nuclear transfer (SCNT) is an attractive field for research, but it has not been a major field of study because it is hard to obtain a sufficient number of ovaries and it takes a lot of time and effort for the recovery of oocytes matured in vivo by ovum pickup. It was reported that the bovine cytoplast could support the remodelling of equine donor cells (Zhou et al. 2007 Reprod. Domest. Anim. 42, 243–247). The objectives of this study are 1) to monitor the early events of equine SCNT by interspecies SCNT (isSCNT) between bovine cytoplast and equine donor cell, and 2) to investigate the developmental competence of isSCNT embryos. Bovine oocytes were recovered from the follicles of slaughtered ovaries, and matured in TCM-199 supplemented with 10 mU mL–1 FSH, 50 ng mL–1 EGF, and 10% FBS at 39°C under 5% CO2 in air for 22 h. Fibroblasts derived from bovine or equine skin tissues were synchronized at G0/G1 stage by contact inhibition for 72 h. After IVM, oocytes with polar body were enucleated and electrically fused with equine or bovine skin fibroblasts (1.0 kV cm–1, 20 μs, 2 pulses). Fused couplets were activated with 5 μM ionomycin for 4 min followed by 5 h culture in 10 μg mL–1 cycloheximide (CHX) and/or 2 mM 6-DMAP, and cultured in modified synthetic oviduct fluid (mSOF) at 39°C under 5% CO2, 5% O2, and 90% N2 for 7 days. All analyses were performed using SAS (version 9.1; SAS Institute, Cary, NC, USA). The cleavage rate of isSCNT embryos derived from equine cell was not different (252/323, 78.7%; P = 0.94) from that of SCNT embryos derived from bovine cell (230/297, 79.2%). However, the rate of isSCNT embryos developed to over 8-cell stage was lower (3.3%; P < 0.0001) than that of bovine SCNT embryos (39.4%), and total cell number of isSCNT embryos developed to over 8-cell stage was lower (17.5, n = 12; P < 0.0001) than that (80.8, n = 110) of bovine SCNT embryos. Also, the rate of blastocyst formation of isSCNT embryos (0/323; 0.0%) was lower (P < 0.0001) than that of bovine SCNT embryos (83/297; 29.3%). Meanwhile, reconstructed oocytes for isSCNT were fixed at 8 h after activation to investigate the formation of pseudo-pronucleus (PPN) after post-activation treatment with CHX or CHX+6-DMAP. The ratio of oocytes with single PPN after treatment with CHX+6-DMAP (26/35; 74.3%) was not different (P = 0.63) from that of oocytes treated with CHX (24/36; 68.1%). Although isSCNT embryos derived from bovine cytoplast and equine donor cell could not develop to more than the 16-cell stage, it is believed that the results of this isSCNT study could be used for the preliminary data regarding the reprogramming of donor cell in equine SCNT.


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