Involved in light signaling, probably by mediating the transport and correct distribution of protoporphyrin IX, a chlorophyll precursor, in response to far-red light. By PHYA. Plant have an enhanced hypocotyl elongation in far-red light, and accumulates protoporphyrin IX. Belongs to the UPF0051 (ycf24) family. Was originally (PubMed:11346655) thought to belong to the ABC transporter family. Lacks the conserved ABC domain, which is one of the features of the ABC transporter family.