ADP-ribosylation factor-like 2 binding protein (ARL2BP)

ADP-ribosylation factor-like 2 binding protein (ARL2BP), also known as BART, is a highly conserved ciliary protein that acts as an effector for the small GTPase ARL2[1][2]. ARL2BP binds specifically to the GTP-bound form of ARL2, but not to ARL2.GDP or other related GTPases[1][2]. It localizes to the basal body and cilium-associated centriole, particularly in photoreceptors and sperm, where it is critical for the assembly and elongation of microtubule doublets in the axoneme[1][2]. This structural role is essential for normal cilia and flagella morphology and function. Loss or mutation of ARL2BP leads to abnormal cilia formation, shortened axonemes, and cellular dysfunction causing severe retinal degeneration (e.g., retinitis pigmentosa), rod-cone dystrophy, male infertility due to sperm flagellar defects, and additional syndromic ciliopathies such as situs inversus and hydrocephalus[1][2][3]. While ARL2BP interacts with ARL2 and may help guide its localization in ciliated tissues, its main function appears to be independent, acting in cytoskeletal structure and stability of microtubules of the ciliary axoneme. There are currently no drugs or direct therapeutic strategies targeting ARL2BP.

Other names

BARTBART1RP66RP82Binder of ARF2 protein 1binder of Arl2ARL2-binding proteinADP-ribosylation factor-like protein 2-binding proteinArf-like 2 binding protein BART1retinitis pigmentosa 66 (autosomal recessive)ADP ribosylation factor like GTPase 2 binding protein