{"title":"FilGAP,Rac1的一种GAP,下调乳腺癌症细胞内隐泡形成。","authors":"Koji Saito, Sakino Ozawa, Yosuke Chiba, Ruri Takahashi, Ryoya Ogomori, Kojiro Mukai, Tomohiko Taguchi, Hiroyasu Hatakeyama, Yasutaka Ohta","doi":"10.1247/csf.23032","DOIUrl":null,"url":null,"abstract":"<p><p>Invadopodia are protrusive structures that mediate the extracellular matrix (ECM) degradation required for tumor invasion and metastasis. Rho small GTPases regulate invadopodia formation, but the molecular mechanisms of how Rho small GTPase activities are regulated at the invadopodia remain unclear. Here we have identified FilGAP, a GTPase-activating protein (GAP) for Rac1, as a negative regulator of invadopodia formation in tumor cells. Depletion of FilGAP in breast cancer cells increased ECM degradation and conversely, overexpression of FilGAP decreased it. FilGAP depletion promoted the formation of invadopodia with ECM degradation. In addition, FilGAP depletion and Rac1 overexpression increased the emergence of invadopodia induced by epidermal growth factor, whereas FilGAP overexpression suppressed it. Overexpression of GAP-deficient FilGAP mutant enhanced invadopodia emergence as well as FilGAP depletion. The pleckstrin-homology (PH) domain of FilGAP binds phosphatidylinositol 3,4-bisphosphate [PI(3,4)P<sub>2</sub>], which is distributed on membranes of the invadopodia. FilGAP localized to invadopodia in breast cancer cells on the ECM, but FilGAP mutant lacking PI(3,4)P<sub>2</sub>-binding showed low localization. Similarly, the decrease of PI(3,4)P<sub>2</sub> production reduced the FilGAP localization. Our results suggest that FilGAP localizes to invadopodia through its PH domain binding to PI(3,4)P<sub>2</sub> and down-regulates invadopodia formation by inactivating Rac1, inhibiting ECM degradation in invasive tumor cells.Key words: invadopodia, breast carcinoma, Rac1, FilGAP, PI(3,4)P<sub>2</sub>.</p>","PeriodicalId":9927,"journal":{"name":"Cell structure and function","volume":" ","pages":"161-174"},"PeriodicalIF":2.0000,"publicationDate":"2023-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11496788/pdf/","citationCount":"0","resultStr":"{\"title\":\"FilGAP, a GAP for Rac1, down-regulates invadopodia formation in breast cancer cells.\",\"authors\":\"Koji Saito, Sakino Ozawa, Yosuke Chiba, Ruri Takahashi, Ryoya Ogomori, Kojiro Mukai, Tomohiko Taguchi, Hiroyasu Hatakeyama, Yasutaka Ohta\",\"doi\":\"10.1247/csf.23032\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Invadopodia are protrusive structures that mediate the extracellular matrix (ECM) degradation required for tumor invasion and metastasis. Rho small GTPases regulate invadopodia formation, but the molecular mechanisms of how Rho small GTPase activities are regulated at the invadopodia remain unclear. Here we have identified FilGAP, a GTPase-activating protein (GAP) for Rac1, as a negative regulator of invadopodia formation in tumor cells. Depletion of FilGAP in breast cancer cells increased ECM degradation and conversely, overexpression of FilGAP decreased it. FilGAP depletion promoted the formation of invadopodia with ECM degradation. In addition, FilGAP depletion and Rac1 overexpression increased the emergence of invadopodia induced by epidermal growth factor, whereas FilGAP overexpression suppressed it. Overexpression of GAP-deficient FilGAP mutant enhanced invadopodia emergence as well as FilGAP depletion. The pleckstrin-homology (PH) domain of FilGAP binds phosphatidylinositol 3,4-bisphosphate [PI(3,4)P<sub>2</sub>], which is distributed on membranes of the invadopodia. FilGAP localized to invadopodia in breast cancer cells on the ECM, but FilGAP mutant lacking PI(3,4)P<sub>2</sub>-binding showed low localization. Similarly, the decrease of PI(3,4)P<sub>2</sub> production reduced the FilGAP localization. Our results suggest that FilGAP localizes to invadopodia through its PH domain binding to PI(3,4)P<sub>2</sub> and down-regulates invadopodia formation by inactivating Rac1, inhibiting ECM degradation in invasive tumor cells.Key words: invadopodia, breast carcinoma, Rac1, FilGAP, PI(3,4)P<sub>2</sub>.</p>\",\"PeriodicalId\":9927,\"journal\":{\"name\":\"Cell structure and function\",\"volume\":\" \",\"pages\":\"161-174\"},\"PeriodicalIF\":2.0000,\"publicationDate\":\"2023-09-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11496788/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Cell structure and function\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1247/csf.23032\",\"RegionNum\":4,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2023/7/22 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q4\",\"JCRName\":\"CELL BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cell structure and function","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1247/csf.23032","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/7/22 0:00:00","PubModel":"Epub","JCR":"Q4","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
FilGAP, a GAP for Rac1, down-regulates invadopodia formation in breast cancer cells.
Invadopodia are protrusive structures that mediate the extracellular matrix (ECM) degradation required for tumor invasion and metastasis. Rho small GTPases regulate invadopodia formation, but the molecular mechanisms of how Rho small GTPase activities are regulated at the invadopodia remain unclear. Here we have identified FilGAP, a GTPase-activating protein (GAP) for Rac1, as a negative regulator of invadopodia formation in tumor cells. Depletion of FilGAP in breast cancer cells increased ECM degradation and conversely, overexpression of FilGAP decreased it. FilGAP depletion promoted the formation of invadopodia with ECM degradation. In addition, FilGAP depletion and Rac1 overexpression increased the emergence of invadopodia induced by epidermal growth factor, whereas FilGAP overexpression suppressed it. Overexpression of GAP-deficient FilGAP mutant enhanced invadopodia emergence as well as FilGAP depletion. The pleckstrin-homology (PH) domain of FilGAP binds phosphatidylinositol 3,4-bisphosphate [PI(3,4)P2], which is distributed on membranes of the invadopodia. FilGAP localized to invadopodia in breast cancer cells on the ECM, but FilGAP mutant lacking PI(3,4)P2-binding showed low localization. Similarly, the decrease of PI(3,4)P2 production reduced the FilGAP localization. Our results suggest that FilGAP localizes to invadopodia through its PH domain binding to PI(3,4)P2 and down-regulates invadopodia formation by inactivating Rac1, inhibiting ECM degradation in invasive tumor cells.Key words: invadopodia, breast carcinoma, Rac1, FilGAP, PI(3,4)P2.
期刊介绍:
Cell Structure and Function is a fully peer-reviewed, fully Open Access journal. As the official English-language journal of the Japan Society for Cell Biology, it is published continuously online and biannually in print.
Cell Structure and Function publishes important, original contributions in all areas of molecular and cell biology. The journal welcomes the submission of manuscripts on research areas such as the cell nucleus, chromosomes, and gene expression; the cytoskeleton and cell motility; cell adhesion and the extracellular matrix; cell growth, differentiation and death; signal transduction; the protein life cycle; membrane traffic; and organelles.