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Essential roles of COUP-TFII in Leydig cell differentiation and male fertility.

Qin J, Tsai MJ, Tsai SY - PLoS ONE (2008)

Bottom Line: Notably, the rescued results also provide the evidence that the major function of adult Leydig cell is to synthesize testosterone.On the other hand, when COUP-TFII is deleted in the adult stage after Leydig cells are well differentiated, there are no obvious defects in reproduction and Leydig cell function.Taken together, these results indicate that COUP-TFII plays a major role in differentiation, but not the maintenance of Leydig cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.

ABSTRACT
Chicken Ovalbumin Upstream Promoter-Transcription Factor II (COUP-TFII; also known as NR2F2), is an orphan nuclear receptor of the steroid/thyroid hormone receptor superfamily. COUP-TFII- mice die during the early embryonic development due to angiogenesis and cardiovascular defects. To circumvent the early embryonic lethality and investigate the physiological function of COUP-TFII, we knocked out COUP-TFII gene in a time-specific manner by using a tamoxifen inducible Cre recombinase. The ablation of COUP-TFII during pre-pubertal stages of male development results in infertility, hypogonadism and spermatogenetic arrest. Homozygous adult male mutants are defective in testosterone synthesis, and administration of testosterone could largely rescue the mutant defects. Notably, the rescued results also provide the evidence that the major function of adult Leydig cell is to synthesize testosterone. Further phenotypic analysis reveals that Leydig cell differentiation is arrested at the progenitor cell stage in the testes of mice. The failure of testosterone to resumption of Leydig cell maturation in the mice indicates that COUP-TFII itself is essential for this process. In addition, we identify that COUP-TFII plays roles in progenitor Leydig cell formation and early testis organogenesis, as demonstrated by the ablation of COUP-TFII at E18.5. On the other hand, when COUP-TFII is deleted in the adult stage after Leydig cells are well differentiated, there are no obvious defects in reproduction and Leydig cell function. Taken together, these results indicate that COUP-TFII plays a major role in differentiation, but not the maintenance of Leydig cells.

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Inducible Ablation of COUP-TFII at Pre-puberty Stage Leads to Infertility and Hypogonadism.A) Scheme of inducible ablation of COUP-TFII at Pre-puberty stage. Tamoxifen or oil was intraperitonealy injected into P14 animals to induce the deletion of COUP-TFII gene, and mice were sacrificed at P90. B) Immunoblotting of COUP-TFII was performed to examine the deletion efficiency in mutant mice, and tissues were collected from the comparison littermates. F/F, Tam: COUP-TFflox/flox treated with tamoxifen: Cre/+ F/F, Oil: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with oil and Cre/+ F/F, Tam: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with tamoxifen. C) The photograph depicts the appearance of male reproduction organs from 3-month-old littermate. D) Relative weight of reproduction organs normalized with body weight. Results are expressed as the mean (±SD) of the ratios for each genotype. Statistical comparison was done with a student test. * P<0.05, ** P<0.01
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pone-0003285-g001: Inducible Ablation of COUP-TFII at Pre-puberty Stage Leads to Infertility and Hypogonadism.A) Scheme of inducible ablation of COUP-TFII at Pre-puberty stage. Tamoxifen or oil was intraperitonealy injected into P14 animals to induce the deletion of COUP-TFII gene, and mice were sacrificed at P90. B) Immunoblotting of COUP-TFII was performed to examine the deletion efficiency in mutant mice, and tissues were collected from the comparison littermates. F/F, Tam: COUP-TFflox/flox treated with tamoxifen: Cre/+ F/F, Oil: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with oil and Cre/+ F/F, Tam: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with tamoxifen. C) The photograph depicts the appearance of male reproduction organs from 3-month-old littermate. D) Relative weight of reproduction organs normalized with body weight. Results are expressed as the mean (±SD) of the ratios for each genotype. Statistical comparison was done with a student test. * P<0.05, ** P<0.01

Mentions: Cre-ERTM (+/−) COUP-TFIIflox/flox mice were generated by crossing CAGG Cre-ERTM mice [32] with COUP-TFIIflox/flox mice. To induce the deletion of COUP-TFII gene, one group of P14 Cre-ERTM (+/−) COUP-TFIIflox/flox animals were injected intraperitoneally with tamoxifen, while another group received only the corn oil carrier to serve as controls. A third group of COUP-TFIIflox/flox animals received IP tamoxifen to ascertain the effect of tamoxifen independent of the activation of the Cre recombinase (Fig. 1A). After COUP-TFII was deleted at P14, our initial observation was that 3-month-old male mutant mice displayed hypoplastic external genitalia (data not shown), suggesting possible defects in reproduction. To test this hypothesis, tamoxifen-treated Cre-ERTM (+/−) COUP-TFIIflox/flox male mice and control male mice, including COUP-TFIIflox/flox and Cre-ERTM (+/−) COUP-TFIIflox/+ mice treated with tamoxifen, and Cre-ERTM (+/−) COUP-TFIIflox/flox treated with oil, were mated with wild-type females and the breeding capacity of each groups were monitored for 3 months. As shown in Table 1, no pups were born from females mated with the mutant males. In addition, we observed the majority of mutant mice failed to impregnate their mates, because vaginal plugs were not found after mating. In contrast, all types of control mice gave birth regularly, and the litter sizes did not differ significantly.


Essential roles of COUP-TFII in Leydig cell differentiation and male fertility.

Qin J, Tsai MJ, Tsai SY - PLoS ONE (2008)

Inducible Ablation of COUP-TFII at Pre-puberty Stage Leads to Infertility and Hypogonadism.A) Scheme of inducible ablation of COUP-TFII at Pre-puberty stage. Tamoxifen or oil was intraperitonealy injected into P14 animals to induce the deletion of COUP-TFII gene, and mice were sacrificed at P90. B) Immunoblotting of COUP-TFII was performed to examine the deletion efficiency in mutant mice, and tissues were collected from the comparison littermates. F/F, Tam: COUP-TFflox/flox treated with tamoxifen: Cre/+ F/F, Oil: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with oil and Cre/+ F/F, Tam: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with tamoxifen. C) The photograph depicts the appearance of male reproduction organs from 3-month-old littermate. D) Relative weight of reproduction organs normalized with body weight. Results are expressed as the mean (±SD) of the ratios for each genotype. Statistical comparison was done with a student test. * P<0.05, ** P<0.01
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2553269&req=5

pone-0003285-g001: Inducible Ablation of COUP-TFII at Pre-puberty Stage Leads to Infertility and Hypogonadism.A) Scheme of inducible ablation of COUP-TFII at Pre-puberty stage. Tamoxifen or oil was intraperitonealy injected into P14 animals to induce the deletion of COUP-TFII gene, and mice were sacrificed at P90. B) Immunoblotting of COUP-TFII was performed to examine the deletion efficiency in mutant mice, and tissues were collected from the comparison littermates. F/F, Tam: COUP-TFflox/flox treated with tamoxifen: Cre/+ F/F, Oil: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with oil and Cre/+ F/F, Tam: Cre-ERTM (+/−) COUP-TFIIflox/flox treated with tamoxifen. C) The photograph depicts the appearance of male reproduction organs from 3-month-old littermate. D) Relative weight of reproduction organs normalized with body weight. Results are expressed as the mean (±SD) of the ratios for each genotype. Statistical comparison was done with a student test. * P<0.05, ** P<0.01
Mentions: Cre-ERTM (+/−) COUP-TFIIflox/flox mice were generated by crossing CAGG Cre-ERTM mice [32] with COUP-TFIIflox/flox mice. To induce the deletion of COUP-TFII gene, one group of P14 Cre-ERTM (+/−) COUP-TFIIflox/flox animals were injected intraperitoneally with tamoxifen, while another group received only the corn oil carrier to serve as controls. A third group of COUP-TFIIflox/flox animals received IP tamoxifen to ascertain the effect of tamoxifen independent of the activation of the Cre recombinase (Fig. 1A). After COUP-TFII was deleted at P14, our initial observation was that 3-month-old male mutant mice displayed hypoplastic external genitalia (data not shown), suggesting possible defects in reproduction. To test this hypothesis, tamoxifen-treated Cre-ERTM (+/−) COUP-TFIIflox/flox male mice and control male mice, including COUP-TFIIflox/flox and Cre-ERTM (+/−) COUP-TFIIflox/+ mice treated with tamoxifen, and Cre-ERTM (+/−) COUP-TFIIflox/flox treated with oil, were mated with wild-type females and the breeding capacity of each groups were monitored for 3 months. As shown in Table 1, no pups were born from females mated with the mutant males. In addition, we observed the majority of mutant mice failed to impregnate their mates, because vaginal plugs were not found after mating. In contrast, all types of control mice gave birth regularly, and the litter sizes did not differ significantly.

Bottom Line: Notably, the rescued results also provide the evidence that the major function of adult Leydig cell is to synthesize testosterone.On the other hand, when COUP-TFII is deleted in the adult stage after Leydig cells are well differentiated, there are no obvious defects in reproduction and Leydig cell function.Taken together, these results indicate that COUP-TFII plays a major role in differentiation, but not the maintenance of Leydig cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA.

ABSTRACT
Chicken Ovalbumin Upstream Promoter-Transcription Factor II (COUP-TFII; also known as NR2F2), is an orphan nuclear receptor of the steroid/thyroid hormone receptor superfamily. COUP-TFII- mice die during the early embryonic development due to angiogenesis and cardiovascular defects. To circumvent the early embryonic lethality and investigate the physiological function of COUP-TFII, we knocked out COUP-TFII gene in a time-specific manner by using a tamoxifen inducible Cre recombinase. The ablation of COUP-TFII during pre-pubertal stages of male development results in infertility, hypogonadism and spermatogenetic arrest. Homozygous adult male mutants are defective in testosterone synthesis, and administration of testosterone could largely rescue the mutant defects. Notably, the rescued results also provide the evidence that the major function of adult Leydig cell is to synthesize testosterone. Further phenotypic analysis reveals that Leydig cell differentiation is arrested at the progenitor cell stage in the testes of mice. The failure of testosterone to resumption of Leydig cell maturation in the mice indicates that COUP-TFII itself is essential for this process. In addition, we identify that COUP-TFII plays roles in progenitor Leydig cell formation and early testis organogenesis, as demonstrated by the ablation of COUP-TFII at E18.5. On the other hand, when COUP-TFII is deleted in the adult stage after Leydig cells are well differentiated, there are no obvious defects in reproduction and Leydig cell function. Taken together, these results indicate that COUP-TFII plays a major role in differentiation, but not the maintenance of Leydig cells.

Show MeSH
Related in: MedlinePlus