RESUMEN
Meiotic resumption-coupled degradation of maternal transcripts occurs during oocyte maturation in the absence of mRNA transcription. The CCR4-NOT complex has been identified as the main eukaryotic mRNA deadenylase. In vivo functional and mechanistic information regarding its multiple subunits remains insufficient. Cnot6l, one of four genes encoding CCR4-NOT catalytic subunits, is preferentially expressed in mouse oocytes. Genetic deletion of Cnot6l impaired deadenylation and degradation of a subset of maternal mRNAs during oocyte maturation. Overtranslation of these undegraded mRNAs caused microtubule-chromosome organization defects, which led to activation of spindle assembly checkpoint and meiotic cell cycle arrest at prometaphase. Consequently, Cnot6l-/- female mice were severely subfertile. The function of CNOT6L in maturing oocytes is mediated by RNA-binding protein ZFP36L2, not maternal-to-zygotic transition licensing factor BTG4, which interacts with catalytic subunits CNOT7 and CNOT8 of CCR4-NOT Thus, recruitment of different adaptors by different catalytic subunits ensures stage-specific degradation of maternal mRNAs by CCR4-NOT This study provides the first direct genetic evidence that CCR4-NOT-dependent and particularly CNOT6L-dependent decay of selective maternal mRNAs is a prerequisite for meiotic maturation of oocytes.
Asunto(s)
Meiosis , Oocitos/metabolismo , Estabilidad del ARN , ARN Mensajero/metabolismo , Ribonucleasas/metabolismo , Animales , Exorribonucleasas , Femenino , Eliminación de Gen , Ratones , Ratones Noqueados , Oocitos/citología , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/genética , Proteínas Represoras , Ribonucleasas/genética , Tristetraprolina/genética , Tristetraprolina/metabolismoRESUMEN
Anther development and male fertility are essential biological processes for flowering plants and are important for crop seed production. Genetic manipulation of male fertility/sterility is critical for crop hybrid breeding. Rice (Oryza sativa L.) male sterility phenotypes, including genic male sterility, hybrid male sterility, and cytoplasmic male sterility, are generally caused by mutations of fertility-related genes, by incompatible interactions between divergent allelic or non-allelic genes, or by genetic incompatibilities between cytoplasmic and nuclear genomes. Here, we review the recent advances in the molecular basis of anther development and male fertility-sterility conversion in specific genetic backgrounds, and the interactions with certain environmental factors. The highlighted findings in this review have significant implications in both basic studies and rice genetic improvement.
Asunto(s)
Oryza/fisiología , Polen , Oryza/genética , ReproducciónRESUMEN
A new difunctional Zn(II) coordination polymer (CP) with the chemical formula of [Zn(TBTA) (L)1.5]n (1) has been synthesized hydrothermally from tetrabromoterephthalic acid (H2TBTA) and 4,4'-bis(imidazole-1-yl)-biphenyl (L) ligands. Furthermore, due to its strong intense emission and open N donor sites, complex 1 could be used as a light-emitting sensor to determine 2,4,6-trinitrophenol (TNP) which has high selectivity and sensitivity. Furthermore, the anti-bacterial effect of the compound against P. gingivalis in vitro was evaluated by measuring the P. gingivalis growth curves after compound treatment. And the RT-PCR assay was performed to detect the relative expression of ragA and ragB, which are important for the P. gingivalis growth. The potential anti-infectious mechanism was further studied by using molecular docking technique.
Asunto(s)
Enfermedades Periodontales/tratamiento farmacológico , Porphyromonas gingivalis/crecimiento & desarrollo , Trinitrobencenos/química , Trinitrobencenos/uso terapéutico , Compuestos de Zinc/química , Compuestos de Zinc/uso terapéutico , Depresión Química , Humanos , Ligandos , Enfermedades Periodontales/microbiología , Polímeros , Trinitrobencenos/farmacología , Compuestos de Zinc/farmacologíaRESUMEN
During mammalian oocyte growth, chromatin configuration transition from the nonsurrounded nucleolus (NSN) to surrounded nucleolus (SN) type plays a key role in the regulation of gene expression and acquisition of meiotic and developmental competence by the oocyte. Nonetheless, the mechanism underlying chromatin configuration maturation in oocytes is poorly understood. Here we show that nucleolar protein DCAF13 is an important component of the ribosomal RNA (rRNA)-processing complex and is essential for oocyte NSN-SN transition in mice. A conditional knockout of Dcaf13 in oocytes led to the arrest of oocyte development in the NSN configuration, follicular atresia, premature ovarian failure, and female sterility. The DCAF13 deficiency resulted in pre-rRNA accumulation in oocytes, whereas the total mRNA level was not altered. Further exploration showed that DCAF13 participated in the 18S rRNA processing in growing oocytes. The lack of 18S rRNA because of DCAF13 deletion caused a ribosome assembly disorder and then reduced global protein synthesis. DCAF13 interacted with a protein of the core box C/D ribonucleoprotein, fibrillarin, i.e., a factor of early pre-rRNA processing. When fibrillarin was knocked down in the oocytes from primary follicles, follicle development was inhibited as well, indicating that an rRNA processing defect in the oocyte indeed stunts chromatin configuration transition and follicle development. Taken together, these results elucidated the in vivo function of novel nucleolar protein DCAF13 in maintaining mammalian oogenesis.