Protein with chaperone functions important for the control of protein folding, processing, stability and localization as well as for the reduction of misfolded protein aggregates. Involved in the regulation of synaptic vesicle recycling, controls STON2 protein stability in collaboration with the COP9 signalosome complex (CSN). In the nucleus, may link the cytoskeleton with the nuclear envelope, this mechanism seems to be crucial for the control of nuclear polarity, cell movement and, specifically in neurons, nuclear envelope integrity. Participates in the cellular trafficking and may regulate the subcellular location of multipass membrane proteins such as the dopamine transporter SLC6A3, leading to the modulation of dopamine neurotransmission. In the endoplasmic reticulum, plays a role in the quality control of protein folding by increasing clearance of misfolded proteins such as SGCE variants or holding them in an intermediate state for proper refolding. May have a redundant function with TOR1B in non-neural tissues (By similarity). ATP + H2O = ADP + H(+) + phosphate Homohexamer. Interacts with TOR1B; the interaction may be specific of neural tissues. Interacts (ATP-bound) with TOR1AIP1 and TOR1AIP2; the interactions induce ATPase activity. Interacts with KLHL14; preferentially when ATP-free. Interacts with KLC1 (via TPR repeats); the interaction associates TOR1A with the kinesin oligomeric complex. Interacts with COPS4; the interaction associates TOR1A with the CSN complex. Interacts with SNAPIN; the interaction is direct and associates SNAPIN with the CSN complex. Interacts with STON2. Interacts (ATP-bound) with SYNE3 (via KASH domain); the interaction is required for SYNE3 nuclear envelope localization. Interacts with VIM; the interaction associates TOR1A with the cytoskeleton. Interacts with PLEC. Interacts (ATP-bound) with SLC6A3; regulates SLC6A3 transport to the plasma membrane (By similarity). Peripherally associated with the inner face of the ER membrane, probably mediated by the interaction with TOR1AIP1. The association with nucleus membrane is mediated by the interaction with TOR1AIP2. Upon oxidative stress, redistributes to protusions from the cell surface (By similarity). N-glycosylated. Belongs to the ClpA/ClpB family. Torsin subfamily.