Clinical and genetic analysis of a patient with periventricular nodular heterotopia 7 caused by NEDD4L gene variant / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis of a patient featuring global developmental delay, intellectual disability, cleft palate, seizures and hypotonia.@*METHODS@#Clinical examination and laboratory tests were carried out. Peripheral blood samples were obtained from the patient and his parents. Whole genomic DNA was extracted and subjected to next generation sequencing. Candidate variation was analyzed by using bioinformatic software and validated by Sanger sequencing.@*RESULTS@#The proband was found to carry a heterozygous c.2117T>C (p.Leu706Pro) variant of the NEDD4L gene, which was a de novo variant validated by Sanger sequencing and predicted to be likely pathogenic according to the American College of Medical Genetics Guidelines.@*CONCLUSION@#The heterozygous variant of c.2117T>C (p.Leu706Pro) of the NEDD4L gene probably underlies the disorders in the patient.

Association of NEDD4 gene polymorphisms with schizophrenia and its clinical characteristics in Chinese Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association of neural precursor cell expressed developmentally down-regulated 4 (NEDD4) with schizophrenia.</p><p><b>METHODS</b>Five single nucleotide polymorphisms (SNPs) of the NEDD4 gene were genotyped by TaqMan SNP genotyping assay in an independent sample of 464 individuals with schizophrenia and 487 healthy controls from eastern Han Chinese population. Clinical data were collected with a general information questionnaire and Positive and Negative Syndrome Scale (PANSS).</p><p><b>RESULTS</b>Frequencies of rs3088077 (allelic: χ2=18.024, P=0.000; genotypic: χ2=16.634, P=0.000), rs7162435 (allelic: χ2=6.771, P=0.009; genotypic: χ2=7.352, P=0.025) and rs2303579 (allelic: χ2=11.253, P=0.001; genotypic: χ2=12.248, P=0.002) were found to be significant different between the two groups. Moreover, TT of rs7162435 was significantly correlated with scores of factors of excitement and hostility (14.53±3.925, F=3.551, P=0.029).</p><p><b>CONCLUSION</b>rs3088077, rs7162435 and rs2303579 of the NEDD4 gene may be associated with schizophrenia. Moreover, the TT genotype of rs7162435 may increase the severity of excitement and hostility. Our results may provide a clue for delineating the connection between the glutamate hypothesis of schizophrenia and ubiquitination.</p>

Upregulation of SIRT1 by 17β-estradiol depends on ubiquitin-proteasome degradation of PPAR-γ mediated by NEDD4-1

17β-estradiol (E2) treatment of cells results in an upregulation of SIRT1 and a down-regulation of PPARγ. The decrease in PPARγ expression is mediated by increased degradation of PPARγ. Here we report that PPARγ is ubiquitinated by HECT E3 ubiquitin ligase NEDD4-1 and degraded, along with PPARγ, in response to E2 stimulation. The PPARγ interacts with ubiquitin ligase NEDD4-1 through a conserved PPXY-WW binding motif. The WW3 domain in NEDD4-1 is critical for binding to PPARΓ. NEDD4-1 overexpression leads to PPARγ ubiquitination and reduced expression of PPARγ. Conversely, knockdown of NEDD4-1 by specific siRNAs abolishes PPARΓ ubiquitination. These data indicate that NEDD4-1 is the E3 ubiquitin ligase responsible for PPARγ ubiquitination. Here, we show that NEDD4-1 delays cellular senescence by degrading PPARΓ expression. Taken together, our data show that E2 could upregulate SIRT1 expression via promoting the PPARΓ ubiquitination-proteasome degradation pathway to delay the process of cell senescence.

Identification of Nedd4 as a novel regulator in Hedgehog signaling / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Hedgehog (Hh) signaling plays an important role in both embryonic development and postnatal tissue homeostasis. Aberrant Hh activation results in a large variety of cancers. This study was designed to discover novel modulators in Hh signaling pathway.</p><p><b>METHODS</b>We performed yeast-two-hybrid screening and immunoprecipitation to identify the interaction of Nedd4 and Smo. To verify whether Nedd4 is involved in the regulation of Hh signaling, we monitored the activation of Gli-luciferase reporter by overexpressing Nedd4 together with Gli-luciferase reporter. In order to examine the role of endogenous Nedd4 in regulating Hh signaling, we used a short hairpin RNA (shRNA) interference strategy to silence the Nedd4 expression, and then perform dual-luciferase reporter assay. Statistical comparisons were performed by Student's t tests.</p><p><b>RESULTS</b>We showed that Nedd4 binds to Smo in the transfected HEK293 cells. Overexpression of Nedd4 alone did not significantly activate the Gli reporter compared to pcDNA3 control (Nedd4 group: dimethyl sulfoxide (DMSO), relative luciferase unit (RLU) 1.87 ± 0.41). However, Smo agonist (SAG)-stimulated activation of Gli-luciferase reporter was markedly potentiated in Nedd4 transfected cells (Nedd4 group: SAG, RLU 13.49 ± 1.04, P < 0.05), indicating that overexpression of Nedd4 increases Gli luciferase reporter activity and Nedd4-induced activation of Hh signaling is activity dependent. In Nedd4 knockdown NIH 3T3 cells, the luciferase reporter activity was measured basally and after SAG treatment. In scrambled cells, compared to DMSO, SAG could activate reporter activity by (4.16 ± 0.84)-fold. In Nedd4 knockdown cells, the luciferase reporter activation by SAG was significantly inhibited (SAG, RLU 1.72 ± 0.24, P < 0.05); knockdown of Nedd4 did not change the basal activity of luciferase activity (DMSO, RLU 0.86 ± 0.11), suggesting that the loss of Nedd4 expression diminishes Gli-dependent activity in the Hh pathway and the regulation of Nedd4 in the Hh signaling pathway is activity-dependent.</p><p><b>CONCLUSION</b>Nedd4 positively regulates the Hh pathway and provides a potential target for inhibiting Hh signaling in cancer therapy.</p>

Relationship between rs3865418 polymorphism of neural precursor cell expressed developmentally downregulated 4-like gene and obesity in Kazakh general population / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the relationships between rs3865418 polymorphism of neural precursor cell expressed developmentally downregulated 4-like gene and obesity in Kazakh general population.</p><p><b>METHODS</b>Based on a cross-sectional epidemiological study in a Kazakh general population, a case-control study was conducted. The rs3865418 polymorphism in a Kazakh general population (856 subjects, including 364 males and 492 females; 478 in obesity group and 378 in normal control group) was genotyped by TaqMan polymerase chain reaction, and the relationship between rs3865418 polymorphism and obesity was analyzed.</p><p><b>RESULTS</b>The rs3865418 polymorphism was successfully genotyped in 851 Kazakh subjects. The distribution of the genotypes and alleles of rs3865418 polymorphism did not differ significantly between the obesity group and normal control group in terms of general populations, males, and females (all P > 0.05). The waist circumference showed a tendency of C/C > C/T > T/T in males and C/C < C/T < T/T in females, but without statistical significance (P > 0.05).</p><p><b>CONCLUSIONS</b>The rs3865418 polymorphism of neural precursor cell expressed developmentally downregulated 4-like gene may not be associated with obesity in Kazakh general population. In other words, it is not a predisposing factor for obesity in Kazakh.</p>

Association of the rs4149601 polymorphism of NEDD4L gene with obesity in Xinjiang Kazakh population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association of the rs4149601 polymorphisms of neural precursor cell expressed developmentally downregulated 4-like gene (NEDD4L) and obesity in Xinjiang Kazakh population.</p><p><b>METHODS</b>The rs4149601 polymorphism of the NEDD4L gene was genotyped in a Xinjiang Kazakh general population including 856 subjects (aged 30 to 60 years, 478 obese and 378 control individuals).</p><p><b>RESULTS</b>The polymorphism was successfully genotyped in 853 Xinjiang Kazakh subjects. The distribution of the additive model and dominant model (AG+ AA vs. GG) of the rs4149601 polymorphism differed significantly between the case and control in both total and females (all P< 0.05). After adjusting for confounding factors, logistic regression analysis showed that the rs4149601 polymorphism (in dominant model) was significantly associated with obesity (OR= 1.479, 95% CI: 1.103-1.983, P= 0.009) in Kazakh. Covariate variance analysis showed that compared with subjects with AA + AG genotypes, the waist circumference was significantly higher in subjects with GG genotype after adjusting for age, smoking and drinking (P= 0.028).</p><p><b>CONCLUSION</b>The genetic variations of the NEDD4L gene may be associated with obesity in Xinjiang Kazakh general population.</p>

Association between rs4149601 polymorphism and essential hypertension in Kazakh / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the association between a functional rs4149601 polymorphism of neural precursor cell expressed developmentally downregulated 4-like gene (NEDD4L) and essential hypertension in Kazakh.</p><p><b>METHODS</b>In this population-based association study, the genotypes of rs4149601 polymorphism were identified by TaqMan PCR in 883 subjects (male 375 383 hypertensives) and its distribution and relationship to hypertension were studied. The association between haplotype (rs4149601, 296921-296923delTTG, rs2288774 and rs2288775, the last three polymorphisms are representative variations identified from 94 Kazakh hypertensive individuals by screening the functional region of NEDD4L previously) and hypertension was also investigated.</p><p><b>RESULTS</b>The genotype distribution of rs4149601 polymorphism was in Hardy-Weinberg equilibrium. The genotype distribution of rs4149601 polymorphism was similar between the essential hypertension patients and the control individuals (all P > 0.05). In the haplotype-based case-control analysis, the distribution of the haplotypes was not significantly different between the case and the control individuals in total and in male subjects but the frequency of D-C-G-G (296921-3delTTG/rs2288774/rs2288775/rs4149601) haplotype was significantly higher in hypertensive than in control individuals in female (P = 0.026).</p><p><b>CONCLUSION</b>Our results suggested that D-C-G-G haplotype of NEDD4L but not rs4149601 polymorphism was linked with hypertension in Kazakh.</p>

Distribution of genetic variation of neural precursor cell expressed developmentally down-regulated 4 gene in Kazak Chinese and its association with hypertension / 中国医学科学院学报

<p><b>OBJECTIVE</b>To analyze the association between the genetic variations of functional region in neural precursor cell expressed developmentally down-regulated 4 ( NEDD4) gene and hypertension in Kazak Chinese in Xinjiang Uygur Autonomous Region.</p><p><b>METHODS</b>The sequences of NEDD4 gene functional region (all exons, exon-intron boundaries, and the putative promoter region, including the 5'- and 3'-untranslated regions 1 kb) were sequenced in Kazak Chinese patients with hypertension. The representative variations selected were genotyped by TaqMan-PCR method in 938 Kazak individuals, including 451 hypertensive patients and 487 normotensive subjects. The association between genetic variations of NEDD4 and hypertension in Kazak was analyzed.</p><p><b>RESULTS</b>Thirteen novel and 15 known single nucleotide polymorphism (SNPs) or mutations, including 7 missense mutations, were identified at the function region of NEDD4 gene in 94 Kazak patients with hypertension. In the nine representative variations genotyped, 4 rare missense mutations [77291T>G (S189R), 77748 C>T (R342W), 123925C>T (P152L), rs1912403 (76821A>G, M33V)] were not specific for the prevalence of hypertension; in addition, the distribution of 5 common SNPs [77943A>C (N407H), rs2303580 (132882G>A, R607Q), rs8028559 (154845T>C), rs7162435 (164420A>G), and rs11550869 (165622C>G)] and haplotypes were not significantly different between the hypertensive patients and normotensive subjects (P>0.05).</p><p><b>CONCLUSION</b>The NEDD4 gene polymorphisms is no associated with hypertension in Kazak Chinese population.</p>