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Cleft palate only is a common birth defect with high heritability. Only a small fraction of this heritability is explained by the genetic variants identified so far, underscoring the need to investigate other disease mechanisms, such as gene-environment (GxE) interactions and parent-of-origin (PoO) effects. Furthermore, PoO effects may vary across exposure levels (PoOxE effects). Such variation is the focus of this study. We upgraded the R-package Haplin to enable direct tests of PoOxE effects at the genome-wide level. From a previous GWAS, we had genotypes for 550 case-parent trios, of mainly European and Asian ancestry, and data on three maternal exposures (smoking, alcohol, and vitamins). Data were analyzed for Europeans and Asians separately, and also for all ethnicities combined. To account for multiple testing, a false discovery rate method was used, where q-values were generated from the p-values. In the Europeans-only analyses, interactions with maternal smoking yielded the lowest q-values. Two SNPs in the ‘Interactor of little elongation complex ELL subunit 1’ (ICE1) gene had a q-value of 0.14, and five of the 20 most significant SNPs were in the ‘N-acetylated alpha-linked acidic dipeptidase-like 2’ (NAALADL2) gene. No evidence of PoOxE effects was found in the other analyses. The connections to ICE1 and NAALADL2 are novel and warrant further investigation. More generally, the new methodology presented here is easily applicable to other traits and exposures in which a family-based study design has been implemented. [ABSTRACT FROM AUTHOR]

Next-generation sequencing of the exome and genome of prostate cancers has identified numerous genetic alternations. SPOP (Speckle-type POZ Protein) was one of the most frequently mutated genes in primary prostate cancer, suggesting SPOP is a potential driver of prostate cancer development and progression. However, how SPOP mutations contribute to prostate cancer pathogenesis remains poorly understood. SPOP acts as an adaptor protein of the CUL3-RBX1 E3 ubiquitin ligase complex that generally recruits substrates for ubiquitination and subsequent degradation. ER-localized isoform of the formin protein inverted formin 2 (INF2) mediates actin polymerization at ER-mitochondria intersections and facilitates DRP1 recruitment to mitochondria, which is a critical step in mitochondrial fission. Here, we revealed that SPOP recognizes a Ser/Thr (S/T)-rich motif in the C-terminal region of INF2 and triggers atypical polyubiquitination of INF2. These ubiquitination modifications do not lead to INF2 instability, but rather reduces INF2 localization in ER and mitochondrially associated DRP1 puncta formation, therefore abrogates its ability to facilitate mitochondrial fission. INF2 mutant escaping from SPOP-mediated ubiquitination is more potent in prompting mitochondrial fission. Moreover, prostate cancer-associated SPOP mutants increase INF2 localization in ER and promote mitochondrial fission, probably through a dominant-negative effect to inhibit endogenous SPOP. Moreover, INF2 is important for SPOP inactivation-induced prostate cancer cell migration and invasion. These findings reveal novel molecular events underlying the regulation of INF2 function and localization, and provided insights in understanding the relationship between SPOP mutations and dysregulation of mitochondrial dynamics in prostate cancer. [ABSTRACT FROM AUTHOR]

Heat shock proteins (Hsps) play important roles in the environmental adaptation of various organisms. To explore the functions of Hsps in relation to heat stress and development in Cotesia vestalis, a solitary larval endoparasitoid of Plutella xylostella, four heat shock protein genes, CvHsp40, CvHsc70, CvHsp70 and CvHsp90, were cloned and sequenced from C. vestalis by real-time quantitative PCR and RACE. The cDNA sequence of CvHsp40, CvHsc70, CvHsp70 and CvHsp90 were 1473 bp, 2316 bp, 2279 bp and 2663 bp long, which encode proteins with calculated molecular weights (MW) of 39.1 kDa, 71.2 kDa, 70.1 kDa and 83.3 kDa, respectively. Furthermore, the analysis of genomic DNA confirmed that no introns existed in CvHsp40, CvHsp70 and CvHsp90 while two introns were present in CvHsc70. The amino acid sequence analysis of CvHsps indicated that CvHsp40 is a Type II Hsp40 homolog, CvHsp70 and CvHsc70 are the eukaryotic cytoplasmic Hsp70s, and CvHsp90 is the β-isoform of Hsp90. The divergent transcriptional patterns of CvHsp40, CvHsp70 and CvHsp90 in the different developmental stages suggested that CvHsp transcripts were under different mechanisms of regulation during the development of parasitoid larvae. The dramatic increase of transcripts of CvHsp70 at the third-instar larva coincided with its developmental change in this stage, that is, from inside host to outside host. CvHsp40, CvHsc70 and CvHsp70 showed a trend of sex-specific differences of transcript abundance in the adult stage. All CvHsp transcripts in different developmental stages were significantly induced by heat stress, and the lowest transcript abundances appeared around the temperature 27°C, which probably suggest that this is the most favorable temperature for the development of C. vestalis. Our results suggest that the expression of heat shock proteins reflects to some extent the developmental changes and environmental requirements of insects. [ABSTRACT FROM AUTHOR]