RESUMEN
The allosteric regulation triggering the protein's functional activity via conformational changes is an intrinsic function of protein under many physiological and pathological conditions, including cancer. Identification of the biological effects of specific somatic variants on allosteric proteins and the phenotypes that they alter during tumor initiation and progression is a central challenge for cancer genomes in the post-genomic era. Here, we mapped more than 47,000 somatic missense mutations observed in approximately 7,000 tumor-normal matched samples across 33 cancer types into protein allosteric sites to prioritize the mutated allosteric proteins and we tested our prediction in cancer cell lines. We found that the deleterious mutations identified in cancer genomes were more significantly enriched at protein allosteric sites than tolerated mutations, suggesting a critical role for protein allosteric variants in cancer. Next, we developed a statistical approach, namely AlloDriver, and further identified 15 potential mutated allosteric proteins during pan-cancer and individual cancer-type analyses. More importantly, we experimentally confirmed that p.Pro360Ala on PDE10A played a potential oncogenic role in mediating tumorigenesis in non-small cell lung cancer (NSCLC). In summary, these findings shed light on the role of allosteric regulation during tumorigenesis and provide a useful tool for the timely development of targeted cancer therapies.
Asunto(s)
Regulación Alostérica/genética , Sitio Alostérico/genética , Genoma Humano/genética , Mutación Missense/genética , Neoplasias/genética , Proteoma/genética , Proteómica , Carcinogénesis/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/genética , Terapia Molecular Dirigida/métodos , Terapia Molecular Dirigida/tendenciasRESUMEN
Spermatogenesis is a highly coordinated process that requires tightly regulated gene expression programmed by transcription factors and epigenetic modifiers. In this study, we found that nuclear respiratory factor (NRF)-1, a key transcription factor for mitochondrial biogenesis, cooperated with DNA methylation to directly regulate the expression of multiple germ cell-specific genes, including Asz1 In addition, conditional ablation of NRF1 in gonocytes dramatically down-regulated these germline genes, blocked germ cell proliferation, and subsequently led to male infertility in mice. Our data highlight a precise crosstalk between transcriptional regulation by NRF1 and epigenetic modulation during germ cell development and unequivocally demonstrate a novel role of NRF1 in spermatogenesis.-Wang, J., Tang, C., Wang, Q., Su, J., Ni, T., Yang, W., Wang, Y., Chen, W., Liu, X., Wang, S., Zhang, J., Song, H., Zhu, J., Wang, Y. NRF1 coordinates with DNA methylation to regulate spermatogenesis.
Asunto(s)
Metilación de ADN/fisiología , Epigénesis Genética/fisiología , Factor Nuclear 1 de Respiración/metabolismo , Espermatogénesis/fisiología , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Infertilidad Masculina/genética , Infertilidad Masculina/metabolismo , Masculino , Ratones , Ratones Noqueados , Células 3T3 NIH , Factor Nuclear 1 de Respiración/genéticaRESUMEN
Nuage is an electron-dense cytoplasmic structure in germ cells that contains ribonucleoproteins and participates in piRNA biosynthesis. Despite the observation that clustered mitochondria are associated with a specific type of nuage called intermitochondrial cement (pi-body), the importance of mitochondrial functions in nuage formation and spermatogenesis is yet to be determined. We show that a germ cell-specific protein GASZ contains a functional mitochondrial targeting signal and is largely localized at mitochondria both endogenously in germ cells and in somatic cells when ectopically expressed. In addition, GASZ interacts with itself at the outer membrane of mitochondria and promotes mitofusion in a mitofusin/MFN-dependent manner. In mice, deletion of the mitochondrial targeting signal reveals that mitochondrial localization of GASZ is essential for nuage formation, mitochondrial clustering, transposon repression, and spermatogenesis. MFN1 deficiency also leads to defects in mitochondrial activity and male infertility. Our data thus reveal a requirement for GASZ and MFN-mediated mitofusion during spermatogenesis.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , GTP Fosfohidrolasas/metabolismo , Mitocondrias/metabolismo , Espermatogénesis , Proteínas Adaptadoras Transductoras de Señales/química , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Células HEK293 , Células HeLa , Humanos , Masculino , Ratones , Dinámicas Mitocondriales , Membranas Mitocondriales/metabolismo , Unión Proteica , Señales de Clasificación de Proteína , Transporte de ProteínasRESUMEN
Kinases use ATP to phosphorylate substrates; recent findings underscore the additional regulatory roles of ATP. Here, we propose a mechanism for allosteric regulation of Akt1 kinase phosphorylation by ATP. Our 4.7-µs molecular dynamics simulations of Akt1 and its mutants in the ATP/ADP bound/unbound states revealed that ATP occupancy of the ATP-binding site stabilizes the closed conformation, allosterically protecting pT308 by restraining phosphatase access and key interconnected residues on the ATPâpT308 allosteric pathway. Following ATPâADP hydrolysis, pT308 is exposed and readily dephosphorylated. Site-directed mutagenesis validated these predictions and indicated that the mutations do not impair PDK1 and PP2A phosphatase recruitment. We further probed the function of residues around pT308 at the atomic level, and predicted and experimentally confirmed that Akt1(H194R/R273H) double mutant rescues pathology-related Akt1(R273H). Analysis of classical Akt homologs suggests that this mechanism can provide a general model of allosteric kinase regulation by ATP; as such, it offers a potential avenue for allosteric drug discovery.
Asunto(s)
Adenosina Trifosfato/metabolismo , Proteínas Proto-Oncogénicas c-akt/química , Proteínas Proto-Oncogénicas c-akt/genética , Regulación Alostérica , Sitios de Unión , Células HeLa , Humanos , Modelos Moleculares , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Fosforilación , Proteína Fosfatasa 2/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-TransferidoraRESUMEN
Primordial germ cells (PGCs) are the first germ-line population that forms from the proximal epiblast of the developing embryo. Despite their biological importance, the regulatory networks whereby PGCs arise, migrate, and differentiate into gametes during embryonic development remains elusive, largely due to the limited number of germ cells in the early embryo. To elucidate the molecular mechanisms that govern early germ cell development, we utilized an in vitro differentiation model of embryonic stem cells (ESCs) and screened a series of candidate genes with specific expression in the adult reproductive organs. We discovered that gain of function of Gasz, a gene previously reported to participate in meiosis of postnatal spermatocytes, led to the most robust upregulation of PGC formation from both human and murine ESCs. In contrast, Gasz deficiency resulted in pronounced reduction of germ cells during ESC differentiation and decreased expression of MVH and DAZL in genital ridges during early embryonic development. Further analyses demonstrated that GASZ interacted with DAZL, a key germ cell regulator, to synergistically promote germ cell derivation from ESCs. Thus, our data reveal a potential role of GASZ during embryonic germ cell development and provide a powerful in vitro system for dissecting the molecular pathways in early germ cell formation during embryogenesis.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Células Madre Embrionarias/citología , Células Germinativas/citología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Diferenciación Celular/fisiología , Células Madre Embrionarias/metabolismo , Femenino , Células Germinativas/metabolismo , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Regiones Promotoras GenéticasRESUMEN
OBJECTIVE: To observe clinical therapeutic effect of acupuncture on diabetic paralytic squint. METHODS: Seventy-two cases of diabetic paralytic squint were randomly divided into a medication group, an acupuncture group and an acupuncture and medication group. The medication group were treated with intramuscular injection of Methyl vitamin B12 250 microg, once daily; the acupuncture group were treated by acupuncture at different acupoints according to different paralytic muscles of eyes with adjuvant acupoints selected according to symptoms; the acupuncture and medication group were treated with the routine medicine and acupuncture. The treatment was given for 28 days. RESULTS: The total effective rate of 87. 5% in the acupuncture group and 95.7% in the acupuncture and medication group were higher than 54.5% in the medication group (P < 0.05, P < 0.01), with no significant difference between the acupuncture group and the acupuncture and medication group (P > 0.05). CONCLUSION: Acupuncture has a definite therapeutic effect on diabetic paralytic squint, which is better than that of routine medication.