Study On The Role Of MVK C.1126G＞A In The Pathogenesis Of Porokeratosis

Background:Porokeratosis(PK)is a rare hereditary chronic abnormal keratosis.The typical clinical feature is the centrifugal levee ridge edge,and there is a lamellar structure of keratin in histopathology.According to the shape,distribution and clinical process of skin lesions,porokeratosis can be divided into various subtypes,including Disseminated superficial actinic porokeratosis(DSAP),Disseminated superficial porokeratosis(DSP),Plaque porokeratosis(PM)Linear porokeratosis(LP),Porokeratosis punctata palmaris etplantaris(PPPP)and Porokeratosis palmoplantaris et disseminated(PPPD).The main risk factors of porokeratosis are genetic factors.So far,more than 60 mutation sites related to porokeratosis have been found.Using wholegene exon sequencing,we conducted a preliminary study on the collected porokeratosis and verified the known mutation site MVK c.1126G>A of porokeratosis.Through literature search,the relationship between the MVK pathogenic site and the clinical phenotype of porokeratosis is still unknown,and the relationship between MVK c.1126G>A and porokeratosis has not been further confirmed from the cellular and molecular level.Objective:1.Analyze the clinical and histopathological characteristics of two patients with porokeratosis collected this time;To preliminarily analyze whether there is a relationship between MVK c.1126G>A and the clinical phenotype of porokeratosis.2.Establish MVK c.1126G>A gene editing cell model;Through the analysis of the differences in proteomics and transcriptomics of cells before and after gene editing,we can find the differential genes,proteins and pathways that may cause porokeratosis,and provide more research evidence for the treatment of porokeratosis,especially for the development of targeted drugs.Methods:In this study,the clinical data of two patients with sporadic porokeratosis were analyzed and skin histopathological examination was performed;DNA was extracted from peripheral venous blood and sequenced by whole-exome sequencing method.Relevant mutation sites were screened by comparison;Through literature review and combined with previous studies,the mutation site MVK c.1126G>A to be further studied was determined.The growth and differentiation of Ha Ca T cells were observed by microscope;The MVK gene locus c.1126G>A was edited by transposon technology to establish a stable cell model;Total protein and RNA were extracted before and after gene editing for proteomic and transcriptomic analysis,and bioinformatics analysis was performed for differentially expressed proteins(DEPs)and differentially expressed genes(DEGs).Results:The clinical features of one patient were consistent with disseminated superficial actinic porokeratosis,and the pathogenic mutation MVK c.1126G>A was detected.The other case was consistent with disseminated superficial porokeratosis,and the relevant mutation ATP2C1 c.899+4A>T was detected.The typical lamellar structure of keratin was found in both cases.According to the literature retrieval,it is not possible to believe that MVK c.1126G>A is associated with the clinical phenotype of porokeratosis.201 differentially expressed genes were obtained,89 were up-regulated and 112 were down-regulated;Through GO database comparison,these differentially expressed genes are mainly involved in cell growth and biological regulation in biological process(BP);KEGG analysis showed that the differentially expressed genes participated in 145 pathways,of which the most significant pathway was involved in the production of Ig A,and found that the gene PIGR was significantly up-regulated,indicating that PIGR might play an important role in porokeratosis caused by MVK mutation.1618 differentially expressed proteins were obtained by differential expression protein analysis,including 767 up-regulated proteins and 851 down-regulated proteins;Among them,the significantly up-regulated M1VPF6(Tyrosine protein kinase receptor)is involved in cell growth regulation,epithelial cell development,columnar /cubic epithelial cell development and immune process,which may be the related protein of porokeratosis caused by MVK mutation.In addition,corresponding to the results of differential expression gene analysis,the differential expression protein analysis found that P01833(Polymeric munoglobulin receptor)encoded by PIGR may play a role in porokeratosis caused by MVK mutation.Conclusion:1 This study has verified the pathogenic mutation site MVK c.1126G>A of porokeratosis,but it cannot be considered that MVK c.1126G>A is only related to the clinical phenotype of disseminated superficial actinic porokeratosis.2.MVK mutation may be closely related to the pathway involved in Ig A production,and P01833 protein in the pathway may play a role in the pathogenesis of porokeratosis.