The following text describes a protein:
Function:
Phosphatidyl inositol monophosphate binding protein involved in endosomal protein sorting through regulation of the endosomal sorting required for transport (ESCRT) pathway. Required for full activity of the ESCRT-III complex core component shrb/shrub, probably by preventing its inappropriate polymerisation. Required, but not essential, for the efficient generation of intraluminal vesicles (ILVs) in multivesicular bodies (MVBs). Involved in a late stage of the endosomal pathway targeting transmembrane proteins of the plasma membrane for lysosomal degradation. Plays a critical role in regulation of multiple signal transduction pathways, including the Notch and BMP/decapentaplegic (dpp) signaling pathways, through targeting of membrane bound receptors to multivesicular bodies, isolating them from the cytoplasm and targeting them for lysosomal degradation. Involved in targeting N/Notch for endosomal degradation, negatively regulating the Notch signaling pathway. Regulates Notch signaling in imaginal disk cells and follicle cells during oogenesis and multiple developmental processes, including development of wings, veins, legs, eyes and bristles. Restricts the activity of Notch to the dorsoventral (D/V) boundary of the wing imaginal disk. In external sensory organ development regulates Notch signaling during asymmetric cell division and differentiation of sensory organ precursor cells. May be involved in regulation of apoptosis and cell growth independent of Notch signaling. Involved in targeting tkv for endosomal degradation, negatively regulating the BMP/decapentaplegic (dpp) signaling pathway. Regulates the BMP/dpp signaling pathway in follicle cells during oogenesis, but not in imaginal disk cells during wing development. May be involved in differentiation or morphogenesis of peripodial epithelial cells in the developing imaginal disk. Involved in abscission of germline cells during oogenesis.
Subcellular Localization:
Cytoplasm. Cytoplasm, cytosol. Apicolateral cell membrane; Peripheral membrane protein; Cytoplasmic side. Cytoplasm, cell cortex. Endosome. Note=Punctate localization in the cell cortex could indicate vesicle association (Probable). Apico-lateral membrane concentration in polarized epithelial and imaginal disk cells but not in asymmetrically dividing neuroblasts.
Domain:
The C2 domain mediates interaction with monophosphorylated phosphatidylinositols PtdIns[3]P, PtdIns[4]P and PtdIns[5]P, and is required for membrane interaction. C2 domains can mediate membrane interactions in a Ca(2+)-dependent or -independent manner; the l(2)gd1 C2 domain lacks three out of five asparagines that are crucial for Ca(2+) binding (Probable). The C2 domain is required for protein stability and cytoplasmic localization, and is essential for l(2)gd1 function; Contains 4 tandem repeats of the DM14 domain that mediate interaction with the ESCRT-III complex component shrb. The 4 DM14 domains show functional redundancy, particularly domains 1 and 3, however domain 3 is necessary and sufficient for l(2)gd1 function. DM14 domain 3 forms an alpha-helical hairpin loop with a positively charged surface patch that binds a negatively charged surface patch on shrb.
Sequence:
MFSRKKPEPAKRRQHDLSQFGLTEIPDDFDPSAGYGEDDGGDSDLEAELAAITGGEGAKPKPKPKAKLLPASDLDKMIADSLRDVSDDDDDDNLESDPDLLGELSGIGGLEEAEEEEPVAQPPAASEEPVQTFLPTTTVDTLSIIKQRLEMYKQAEANAKTAGDSGKARRFGRGLKTLKDLHRQAAAGKSINVDDIPPEVSVKPIGGQAPPVPAEESPAPSTPASPPPVPSRAAPDPPTPGTPVEPTTSVAPTSPPNPLVTQMRSRQTDYKAAALQSKRSGDISTALQFLKVVKQFDVVIKMCEDGQEVDLSDMPPPPAEFLEFLKKMQEEAAAEAVAEPTAAPEPTPVAPAPVLAAATNMLEALQQRLEKYQSVEAAAKAENNSGKARRFGRIVKQYEDAIKLYKAGKPVPYDELPVPPGFGPLPTADAAPVAPTPSLPTSPTSPPPTASTSAGGTPSSSSATTPTAPRKAPSPPKPKELTTRTSGNQQKNNIAEQQMKLLLERQKEFKLAAIEAKKAGEIDQAKEYLKIFKGFDSLLNAASSGLPVDLSTLPVPPSQRDNLEASFAIVSAEECDPTDDICEIGVRMEEQLAKQLMMCKNTRDHHKAMGDVAGMNRFENLALTVQKDLDLVRYSKRKNEPLPKFHYEKRSFNIVHCNTDLTDSELEIVVVRGISYNVANPKDVDTYVRVEFPLLNDESFKTKTNVIRDTSSPDYDERFKVDIQRTNRQFQRIFKRHGVKFEIYSRGGFLRSDTLIGTVNVKLQPLETKCEIHDTYDLMDGRKQVGGKLEVKIRVRNPILTKQMEHITEKWLVLDA