Analysis of the coding sequence and expression of the coiled-coil α-helical rod protein 1 gene in normal and neoplastic epithelial cervical cells

Segregation of nascent GPCRs in the ER-to-Golgi transport by CCHCR1 via direct interaction

G protein-coupled receptors (GPCRs) constitute the largest superfamily of cell surface signaling proteins that share a common structural topology. When compared with agonist-induced internalization, how GPCRs are sorted and delivered to functional destinations after synthesis in the endoplasmic reticulum (ER) is much less well understood. Here, we demonstrate that depletion of coiled-coil α-helical rod protein 1 (CCHCR1) by siRNA and CRISPR-Cas9 significantly inhibits surface expression and signaling of α2A-adrenergic receptor (α2A-AR; also known as ADRA2A), without affecting α2B-AR. Further studies show that CCHCR1 depletion specifically impedes α2A-AR export from the ER to the Golgi, but not from the Golgi to the surface. We also demonstrate that CCHCR1 selectively interacts with α2A-AR. The interaction is mediated through multiple domains of both proteins and is ionic in nature. Moreover, mutating CCHCR1-binding motifs significantly attenuates ER-to-Golgi export, surface expression and signaling of α2A-AR. Collectively, these data reveal a novel function for CCHCR1 in intracellular protein trafficking, indicate that closely related GPCRs can be sorted into distinct ER-to-Golgi transport routes by CCHCR1 via direct interaction, and provide important insights into segregation and anterograde delivery of nascent GPCR members.

The genomic response of human granulosa cells (KGN) to melatonin and specific agonists/antagonists to the melatonin receptors

Melatonin is a known modulator of follicle development; it acts through several molecular cascades via binding to its two specific receptors MT1 and MT2. Even though it is believed that melatonin can modulate granulosa cell (GC) functions, there is still limited knowledge of how it can act in human GC through MT1 and MT2 and which one is more implicated in the effects of melatonin on the metabolic processes in the dominant follicle. To better characterize the roles of these receptors on the effects of melatonin on follicular development, human granulosa-like tumor cells (KGN) were treated with specific melatonin receptor agonists and antagonists, and gene expression was analyzed with RNA-seq technology. Following appropriate normalization and the application of a fold change cut-off of 1.5 (FC 1.5, p ≤ 0.05) for each treatment, lists of the principal differentially expressed genes (DEGs) are generated. Analysis of major upstream regulators suggested that the MT1 receptor may be involved in the melatonin antiproliferative effect by reprogramming the metabolism of human GC by activating the PKB signaling pathway. Our data suggest that melatonin may act complementary through both MT1 and MT2 receptors to modulate human GC steroidogenesis, proliferation, and differentiation. However, MT2 receptors may be the ones implicated in transducing the effects of melatonin on the prevention of GC luteinization and follicle atresia at the antral follicular stage through stimulating the PKA pathway.

Identification of protein/mRNA network involving the PSORS1 locus gene CCHCR1 and the PSORS4 locus gene HAX1

CCHCR1 (Coiled-Coil alpha-Helical Rod 1), maps to chromosomal region 6p21.3, within the major psoriasis susceptibility locus PSORS1. CCHCR1 itself is a plausible psoriasis candidate gene, however its role in psoriasis pathogenesis remains unclear. We previously demonstrated that CCHCR1 protein acts as a cytoplasmic docking site for RNA polymerase II core subunit 3 (RPB3) in cycling cells, suggesting a role for CCHCR1 in vesicular trafficking between cellular compartments. Here, we report a novel interaction between CCHCR1 and the RNA binding protein HAX1. HAX1 maps to chromosomal region 1q21.3 within the PSORS4 locus and is over-expressed in psoriasis. Both CCHCR1 and HAX1 share subcellular co-localization with mitochondria, nuclei and cytoplasmic vesicles as P-bodies. By a series of ribonucleoprotein immunoprecipitation (RIP) assays, we isolated a pool of mRNAs complexed with HAX1 and/or CCHCR1 proteins. Among the mRNAs complexed with both CCHCR1 and HAX1 proteins, there are Vimentin mRNA, previously described to be bound by HAX1, and CAMP/LL37 mRNA, whose gene product is over-expressed in psoriasis.

Assessment of circulating miR-20b, miR-221, and miR-155 in occupationally lead-exposed workers of North-Western India

Lead (Pb), a toxic heavy metal, is capable of inducing several adverse health effects following its accumulation in the body. Lead is a potential carcinogen, capable of causing multisystem alterations. Recent reports identify small regulatory RNA molecules-miRNAs-which show differential expression in individuals exposed to similar levels of lead. These miRNAs can become potential molecular biomarkers of lead toxicity in the future and may unravel the possible molecular pathways through which this metal may exert its toxic manifestations. The present study aimed to assess the circulating levels of miRNA-20b, 221, and 155 in occupationally lead-exposed workers and correlate them with blood lead levels. One hundred ten participants working in various factories of Jodhpur and 97 participants not occupationally exposed to lead were recruited after obtaining due informed consent. Blood lead level (BLL) was estimated by graphite furnace atomic absorption spectrophotometry (GF-AAS). Circulating miRNAs were isolated from serum by Qiagen miRNA isolation kit and converted to cDNA by commercial kit. Expression profiles of miR-20b, miR-221, and miR-155 were performed in RT-PCR using Qiagen miRNA PCR assays. The blood lead level (mean ± SD) of occupationally lead-exposed subjects was 6.94 ± 11.96 μg/dL while that of non-exposed was 2.39 ± 4.66 μg/dL. Out of the three miRNAs, miR-155 and miR-221 were significantly upregulated, while miR-20b did not show significant difference among study groups. The fold change of miR-20b, miR-221 and miR-155 expression were 1.08, 2.71 and 2.07 respectively. Functional analysis revealed that these miRNAs have the potential to trigger various genes and cellular pathways. The findings of our study highlight the importance of miRNA dysregulation in lead-exposed individuals that may contribute to the systemic effects of lead toxicity.

Do myeloproliferative neoplasms and multiple myeloma share the same genetic susceptibility loci?

Myeloproliferative neoplasms (MPNs) are a group of diseases that cause myeloid hematopoietic cells to overproliferate. Epidemiological and familial studies suggest that genetic factors contribute to the risk of developing MPN, but the genetic susceptibility of MPN is still not well known. Indeed, only few loci are known to have a clear role in the predisposition to this disease. Some studies reported a diagnosis of MPNs and multiple myeloma (MM) in the same patients, but the biological causes are still unclear. We tested the hypothesis that the two diseases share at least partly the same genetic risk loci. In the context of a European multicenter study with 460 cases and 880 controls, we analyzed the effect of the known MM risk loci, individually and in a polygenic risk score (PRS). The most significant result was obtained among patients with chronic myeloid leukemia (CML) for PS0RS1C1-rs2285803, which showed to be associated with an increased risk (OR = 3.28, 95% CI 1.79-6.02, P = .00012, P = .00276 when taking into account multiple testing). Additionally, the PRS showed an association with MPN risk when comparing the last with the first quartile of the PRS (OR = 2.39, 95% CI 1.64-3.48, P = 5.98 × 10^-6 ). In conclusion, our results suggest a potential common genetic background between MPN and MM, which needs to be further investigated.

Identification of differential plasma miRNA profiles in Chinese workers with occupational lead exposure

Elevated lead absorptions are hazardous factors in lead-related workers. Previous studies have found its toxic impacts on nervous, circulatory, and metabolic systems. We hypothesized that alteration of miRNAs profile in plasma was closely associated with lead exposure. We analyzed to identify lead-related miRNAs in workers occupationally exposed to lead. Microarray assay was performed to detect plasma miRNA between workers with high and minimal lead exposure in the discovery stage. The following prediction of miRNAs' candidate target genes was carried out by using miRecords, STRING, and KEGG databases. We finally identified four miRNAs significantly associated with high level of blood lead. miR-520c-3p (*P=0.014), miR-211 (*P=0.019), and miR-148a (*P=0.031) were downexpressed in workers with high lead exposure and with high blood lead level (BLL), while miR-572(*P=0.027) displayed an opposite profile. Functional analysis of miRNAs displayed that these miRNAs could trigger different cellular genes and pathways. People under chronic lead exposure had a diverse 'fingerprint' plasma miRNA profile. Our study suggested that miR-520c-3p, miR-211, miR-148a, and miR-572 were the potential biomarkers for lead susceptibility in Chinese.

CCHCR1 interacts specifically with the E2 protein of human papillomavirus type 16 on a surface overlapping BRD4 binding

The Human Papillomavirus E2 proteins are key regulators of the viral life cycle, whose functions are commonly mediated through protein-protein interactions with the host cell proteome. We identified an interaction between E2 and a cellular protein called CCHCR1, which proved highly specific for the HPV16 genotype, the most prevalent in HPV-associated cancers. Further characterization of the interaction revealed that CCHCR1 binds the N-terminal alpha helices of HPV16 E2 N-terminal domain. On this domain, the CCHCR1 binding interface overlaps that of BRD4, a key mediator of E2 transcriptional activity. Consequently a physical competition occurs between the two proteins for the binding to HPV16 E2, and CCHCR1 interferes with BRD4-mediated enhancement of E2-dependent transcription. In addition, we showed that the interaction with CCHCR1 induced a massive redistribution of HPV16 E2, from a predominantly nuclear to a cytoplasmic localization in dot-like structures, where E2 perfectly co-localizes with CCHCR1. Such a cytoplasmic docking likely interferes with the nuclear functions of HPV16 E2. Upon co-expression of BRD4 and CCHCR1, E2 accumulates both in the nucleus and in the cytoplasm, indicating that for HPV16, both sub-cellular localization and transcriptional functions of E2 may depend on the proportion of both factors within the cell. We provided evidence of a strong induction of the keratinocyte differentiation marker K10 by HPV16 E2, and showed that this activation is compromised by the interaction with CCHCR1. The specific interaction described here could thus impact on the pathogenesis of HPV16. We propose that it could underlie some specific traits of HPV16 infection, such as an enhanced propensity to give rise to lesions evolving toward cancer.

Centrosomal localization of the psoriasis candidate gene product, CCHCR1, supports a role in cytoskeletal organization

CCHCR1 (Coiled-Coil α-Helical Rod protein 1), within the major psoriasis susceptibility locus PSORS1, is a plausible candidate gene with the psoriasis associated risk allele CCHCR1*WWCC. Although its expression pattern in psoriatic skin differs from healthy skin and its overexpression influences cell proliferation in transgenic mice, its role as a psoriasis effector gene has remained unsettled. The 5′-region of the gene contains a SNP (rs3130453) that controls a 5′-extended open reading frame and thus the translation of alternative isoforms. We have now compared the function of two CCHCR1 isoforms: the novel longer isoform 1 and the previously studied isoform 3. In samples of Finnish and Swedish families, the allele generating only isoform 3 shows association with psoriasis (P<10⁻⁷). Both isoforms localize at the centrosome, a cell organelle playing a role in cell division. In stably transfected cells the isoform 3 affects cell proliferation and with the CCHCR1*WWCC allele, also apoptosis. Furthermore, cells overexpressing CCHCR1 show isoform- and haplotype-specific influences in the cell size and shape and alterations in the organization and expression of the cytoskeletal proteins actin, vimentin, and cytokeratins. The isoform 1 with the non-risk allele induces the expression of keratin 17, a hallmark for psoriasis; the silencing of CCHCR1 reduces its expression in HEK293 cells. CCHCR1 also regulates EGF-induced STAT3 activation in an isoform-specific manner: the tyrosine phosphorylation of STAT3 is disturbed in isoform 3-transfected cells. The centrosomal localization of CCHCR1 provides a connection to the abnormal cell proliferation and offers a link to possible cellular pathways altered in psoriasis.