DENND2B
Function
Isoform 1
May be involved in cytoskeletal organization and tumorogenicity. Seems to be involved in a signaling transduction pathway leading to activation of MAPK1/ERK2. Plays a role in EGFR trafficking from recycling endosomes back to the cell membrane (PubMed:29030480).
Isoform 2
Guanine nucleotide exchange factor (GEF) which may activate RAB9A and RAB9B. Promotes the exchange of GDP to GTP, converting inactive GDP-bound Rab proteins into their active GTP-bound form.
Isoform 3
May block ERK2 activation stimulated by ABL1 (Probable). May alter cell morphology and cell growth (Probable).
Post-translational modifications
Phosphorylated. Phosphorylation decreases ITSN1 binding.
Tissue Specificity
Widely expressed with the exception of peripheral blood lymphocytes. Isoform 1 is expressed in several epithelial and fibroblast (including tumorigenic) but absent in lymphoid cell lines (at protein level). Isoform 3 is expressed in primary cell or weakly tumorigenic but not in tumorigenic cell lines (at protein level).
Cellular localization
- Isoform 1
- Cytoplasm
- Cell cortex
- Cell membrane
- Recycling endosome
- Colocalizes with RAB13 and ITSN1 at cytoplasmic vesicles that are most likely recycling endosomes. Colocalizes with the cortical actin cytoskeleton.
Alternative names
HTS1, ST5, DENND2B, DENN domain-containing protein 2B, HeLa tumor suppression 1, Suppression of tumorigenicity 5 protein