Guanine nucleotide exchange factor (GEF) for RHOA and RAC1 GTPases (PubMed:8643598, PubMed:22155786, PubMed:27418539). Involved in coordinating actin remodeling, which is necessary for cell migration and growth (PubMed:10341202, PubMed:22155786). Plays a key role in the regulation of neurite outgrowth and lamellipodia formation (PubMed:32109419). In developing hippocampal neurons, limits dendrite formation, without affecting the establishment of axon polarity. Once dendrites are formed, involved in the control of synaptic function by regulating the endocytosis of AMPA-selective glutamate receptors (AMPARs) at CA1 excitatory synapses (By similarity). May act as a regulator of adipogenesis (By similarity). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Interacts with CARMIL1 (PubMed:19846667). Interacts with PTPRF/LAR (PubMed:8643598). Interacts with ANKRD26 (PubMed:22666460). Interacts with Bassoon/BSN and Piccolo/PCLO (By similarity). Interacts with the cytoplasmic region of the heterodimer formed by NGFR and SORCS2. ProNGF binding mediates dissociation of TRIO from the receptor complex (PubMed:22155786). Widely expressed, with highest levels in heart, skeletal muscle, and brain. The N-terminal DBL/GEF domain specifically catalyzes nucleotide exchange for RAC1, leading to the activation of Jun kinase and the production of membrane ruffles. The second DBL/GEF domain is an exchange factor for rhoa and induces the formation of stress fibers. Phosphorylated on serine residue(s). The disease may be caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family. Truncated N-terminus. Truncated N-terminus.