Receptor for GDNF. Mediates the GDNF-induced autophosphorylation and activation of the RET receptor. 2 molecules of GDNFR-alpha are thought to form a complex with the disulfide-linked GDNF dimer and with 2 molecules of RET (PubMed:15044950). Interacts with RET (By similarity). Interacts with SORL1, either alone or in complex with GDNF. Interaction between SORL1 and GFRA1 leads to GFRA1 internalization, but not degradation (By similarity). Localizes mainly to the plasma membrane. In the presence of SORL1, shifts to vesicular structures, including trans-Golgi network, endosomes and multivesicular bodies. Expressed in liver, brain, kidney and cochlea. Belongs to the GDNFR family.