The development of amyotrophic lateral sclerosis(ALS)may be related to the abnormal alterations of multiple proteins.Our previous study revealed that the expression of phosphoinositide-3-kinase regulatory subunit 4(PI...The development of amyotrophic lateral sclerosis(ALS)may be related to the abnormal alterations of multiple proteins.Our previous study revealed that the expression of phosphoinositide-3-kinase regulatory subunit 4(PIK3R4)was decreased in ALS.However,the role of PIK3R4 in ALS pathogenesis remains unknown.This study was the first to find that transfection of PC12 cells with small interfering RNA against the PIK3R4 gene significantly decreased the expression levels of PIK3R4 and the autophagy-related proteins p62 and LC3.Additionally,in vivo experiments revealed that the PIK3R4 protein was extensively expressed in the anterior horn,posterior horn,central canal,and areas surrounding the central canal in cervical,thoracic,and lumbar segments of the spinal cord in adult mice.PIK3R4 protein was mainly expressed in the neurons within the spinal lumbar segments.PIK3R4 and p62 expression levels were significantly decreased at both the pre-onset and onset stages of ALS disease in Tg(SOD1*G93A)1 Gur mice compared with control mice,but these proteins were markedly increased at the progression stage.LC3 protein expression did not change during progression of ALS.These findings suggest that PIK3R4 likely participates in the prevention of ALS progression.This study was approved by the Ethics Committee for Animal Care and Use of Jiangxi Provincial People’s Hospital,Affiliated People’s Hospital of Nanchang University(approval No.2020025)on March 26,2020.展开更多
Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological ...Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological conditions, including cancer. Many studies have already addressed the role of protein kinases misregulation in cancer. However, much less is known about protein phosphatases influence. Phosphoprotein Phosphatase 1 (PPP1) is one of the major serine/threonine protein phosphatases who has three catalytic isoforms: PPP1CA, PPP1CB, and PPP1CC. Its function is achieved by binding to regulatory subunits, known as PPP1-interacting proteins (PIPs), which may prefer a catalytic isoform. Also, some inhibitors/enhancers may exhibit isoform specificity. Here we show that, prodigiosin (PG), a molecule with anticancer properties, promotes the formation of PPP1CA-AKT complex and not of PPP1CC-MAPK complex. Both, AKT and MAPK, are well-known PIPs from two pathways that crosstalk and regulate melanoma cells survival. In addition, the analysis performed using surface plasmon resonance (SPR) technology indicates that PPP1 interacts with obatoclax (OBX), a drug that belongs to the same family of PG. Overall, these results suggest that PG might, at least in part, act through PPP1C/PIPs. Also, this study is pioneer in demonstrating PPP1 isoform-specific modulation by small molecules.展开更多
基金supported by the National Natural Science Foundation of China(Nos.30560042,81160161 and 81360198)Education Department of Jiangxi Province(No.GJJ170021)+1 种基金Jiangxi Provincial Department of Science and Technology(Nos.[2014]-47,20142BBG70062,20171BAB215022,20192BAB205043)Health Commission of Jiangxi Province(No.20181019)(all to RSX)。
文摘The development of amyotrophic lateral sclerosis(ALS)may be related to the abnormal alterations of multiple proteins.Our previous study revealed that the expression of phosphoinositide-3-kinase regulatory subunit 4(PIK3R4)was decreased in ALS.However,the role of PIK3R4 in ALS pathogenesis remains unknown.This study was the first to find that transfection of PC12 cells with small interfering RNA against the PIK3R4 gene significantly decreased the expression levels of PIK3R4 and the autophagy-related proteins p62 and LC3.Additionally,in vivo experiments revealed that the PIK3R4 protein was extensively expressed in the anterior horn,posterior horn,central canal,and areas surrounding the central canal in cervical,thoracic,and lumbar segments of the spinal cord in adult mice.PIK3R4 protein was mainly expressed in the neurons within the spinal lumbar segments.PIK3R4 and p62 expression levels were significantly decreased at both the pre-onset and onset stages of ALS disease in Tg(SOD1*G93A)1 Gur mice compared with control mice,but these proteins were markedly increased at the progression stage.LC3 protein expression did not change during progression of ALS.These findings suggest that PIK3R4 likely participates in the prevention of ALS progression.This study was approved by the Ethics Committee for Animal Care and Use of Jiangxi Provincial People’s Hospital,Affiliated People’s Hospital of Nanchang University(approval No.2020025)on March 26,2020.
基金supported by grants from Fundacao para a Ciencia e Tecnologia(FCT)of the Portuguese Ministry of Science and Higher Education(PTDC/DTP-PIC/0460/2012)by FEDER through Eixo I do Programa Operacional Fatores de Competitividade(POFC)(FCOMP-01-0124-FEDER-028692)co-funded by QREN
文摘Reversible protein phosphorylation is a central regulatory mechanism of cell function. Deregulation of the balanced actions of protein kinases and phosphatases has been frequently associated with several pathological conditions, including cancer. Many studies have already addressed the role of protein kinases misregulation in cancer. However, much less is known about protein phosphatases influence. Phosphoprotein Phosphatase 1 (PPP1) is one of the major serine/threonine protein phosphatases who has three catalytic isoforms: PPP1CA, PPP1CB, and PPP1CC. Its function is achieved by binding to regulatory subunits, known as PPP1-interacting proteins (PIPs), which may prefer a catalytic isoform. Also, some inhibitors/enhancers may exhibit isoform specificity. Here we show that, prodigiosin (PG), a molecule with anticancer properties, promotes the formation of PPP1CA-AKT complex and not of PPP1CC-MAPK complex. Both, AKT and MAPK, are well-known PIPs from two pathways that crosstalk and regulate melanoma cells survival. In addition, the analysis performed using surface plasmon resonance (SPR) technology indicates that PPP1 interacts with obatoclax (OBX), a drug that belongs to the same family of PG. Overall, these results suggest that PG might, at least in part, act through PPP1C/PIPs. Also, this study is pioneer in demonstrating PPP1 isoform-specific modulation by small molecules.
