Naslov
Dissection of the role of IqgC domains in the cell­ substratum adhesion

Autori
Mijanović, Lucija ; Putar, Darija ; Filić, Vedrana ; Weber, Igor

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
FEBS Open Bio Volume 12 Supplement 1 : The Biochemistry Global Summit, 25th IUBMB Congress, 46th FEBS Congress, 15th PABMB Congress / - , 2022, 205-206

Skup
The Biochemistry Global Summit

Mjesto i datum
Lisabon, Portugal, 06.07.2022. - 14.07.2022

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
cell-substratum adhesion ; Dictyostelium ; IqgC

Sažetak
Cell­-substratum adhesion is important for motility, phagocytosis and cytokinesis of individual cells, as well as complex biological processes in multicellular organisms, such as development, tissue homeostasis and wound healing. In Dictyostelium discoideum, many proteins are involved in establishing the punctiform adhesion structures at the ventral cellular cortex, e. g. talin, paxillin, and Phg2. Protein IqgC is a RasGAP protein that negatively regulates large- scale endocytosis and binds and inactivates small GTPase RasG. We observed that cells deficient for IqgC are more loosely attached to the substratum than wild-­type cells. IqgC possesses two main functional domains – a GRD (GAP-­related domain) and an RGCt (RasGAP C-­terminus). In homologous proteins, like human IQGAP1, GRD domain is important for binding small GTPases, while RGCt binds PtdIns(4, 5)P2, E-­cadherin, and β-­catenin. We therefore set out to determine which of these domains is important for the function of IqgC in adhesion. Cells overexpressing YFP-­IqgC, YFP-­GRD and YFP-­RGCt were examined by confocal microscopy to inspect their localization to the ventral adhesion structures, whereas the IqgC KO cells transfected with deletion constructs lacking each domain were tested for substratum adhesion using a rotational agitation assay. We showed that the full­-length IqgC localizes to the ventral adhesion structures and rescues the adhesion phenotype of IqgC KO cells, while only the RGCt domain localized to the adhesion structures. However, none of the tested truncated constructs was able to rescue the adhesion phenotype of IqgC KO cells. Thus, we concluded that the RGCt domain is sufficient for the localization of IqgC to adhesion structures but the GRD domain also contributes to the establishment of the interactions necessary for the IqgC activity in the cell­-substratum adhesion.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA