Small GTPase which cycles between active GTP-bound and inactive GDP-bound states. In its active state, binds to a variety of effector proteins playing a key role in the regulation of endo-lysosomal trafficking. Governs early-to-late endosomal maturation, microtubule minus-end as well as plus-end directed endosomal migration and positioning, and endosome-lysosome transport through different protein-protein interaction cascades (By similarity). Plays a central role, not only in endosomal traffic, but also in many other cellular and physiological events, such as growth-factor-mediated cell signaling, nutrient-transporter-mediated nutrient uptake, neurotrophin transport in the axons of neurons and lipid metabolism (By similarity). Also involved in regulation of some specialized endosomal membrane trafficking, such as maturation of melanosomes, pathogen-induced phagosomes (or vacuoles) and autophagosomes (By similarity). Plays a role in the maturation and acidification of phagosomes that engulf pathogens, such as S.aureus and Mycobacteria (By similarity). Plays a role in the fusion of phagosomes with lysosomes (By similarity). Plays important roles in microbial pathogen infection and survival, as well as in participating in the life cycle of viruses (By similarity). Microbial pathogens possess survival strategies governed by RAB7A, sometimes by employing RAB7A function (e.g. Salmonella) and sometimes by excluding RAB7A function (e.g. Mycobacterium) (By similarity). In concert with RAC1, plays a role in regulating the formation of RBs (ruffled borders) in osteoclasts (PubMed:16040606). Controls the endosomal trafficking and neurite outgrowth signaling of NTRK1/TRKA (PubMed:16306406). Regulates the endocytic trafficking of the EGF-EGFR complex by regulating its lysosomal degradation (By similarity). Involved in the ADRB2-stimulated lipolysis through lipophagy, a cytosolic lipase-independent autophagic pathway. Required for the exosomal release of SDCBP, CD63 and syndecan (By similarity). Required for vesicular trafficking and cell surface expression of ACE2 (By similarity). May play a role in PRPH neuronal intermediate filament assembly (By similarity). GTP + H2O = GDP + H(+) + phosphate Interacts with NTRK1/TRKA (PubMed:16306406). Interacts with RILP (By similarity). Interacts with PSMA7 (By similarity). Interacts with RNF115 (By similarity). Interacts with and FYCO1 (By similarity). Interacts with the PIK3C3/VPS34-PIK3R4 complex (By similarity). The GTP-bound form interacts with OSBPL1A (By similarity). The GTP-bound form interacts with RAC1 (PubMed:16040606). Interacts with CLN3 (By similarity). Interacts with CHM, the substrate-binding subunit of the Rab geranylgeranyltransferase complex (PubMed:18756270, PubMed:15186776). Interacts with C9orf72 (By similarity). Does not interact with HPS4 and the BLOC-3 complex (heterodimer of HPS1 and HPS4). Interacts with CLN5 (By similarity). Interacts with PLEKHM1 (via N- and C-terminus) (By similarity). Interacts with PRPH; the interaction is direct (By similarity). Interacts with VPS13A (By similarity). The GDP-bound form interacts with RIMOC1 (By similarity). Interacts with the MON1A-CCZ1B complex and this interaction is enhanced in the presence of RIMOC1 (By similarity). Colocalizes with OSBPL1A at the late endosome. Found in the ruffled border (a late endosomal-like compartment in the plasma membrane) of bone-resorbing osteoclasts. Recruited to phagosomes containing S.aureus or Mycobacterium. Lipid droplet localization is increased upon ADRB2 stimulation. Recruited to damaged mitochondria during mitophagy in a RIMOC1-dependent manner. Expressed in osteoclasts and in neurons. Belongs to the small GTPase superfamily. Rab family.