HOOK1

This gene encodes a member of the hook family of coiled-coil proteins, which bind to microtubules and organelles through their N- and C-terminal domains, respectively. The encoded protein localizes to discrete punctuate subcellular structures, and interacts with several members of the Rab GTPase family involved in endocytosis. It is thought to link endocytic membrane trafficking to the microtubule cytoskeleton. Several alternatively spliced transcript variants have been identified, but the full-length nature of some of these variants has not been determined. [provided by RefSeq, Jul 2008]

Hook Microtubule Tethering Protein 1

Component of the FTS/Hook/FHIP complex (FHF complex) (PubMed:18799622, PubMed:32073997).

The FHF complex may function to promote vesicle trafficking and/or fusion via the homotypic vesicular protein sorting complex (the HOPS complex) (PubMed:18799622).

FHF complex promotes the distribution of AP-4 complex to the perinuclear area of the cell (PubMed:32073997).

Required for spermatid differentiation. Probably involved in the positioning of the microtubules of the manchette and the flagellum in relation to the membrane skeleton (By similarity).

Cytoplasmic microtubule organization Source: GO_Central
Cytoskeleton-dependent intracellular transport Source: GO_Central
Early endosome to late endosome transport Source: UniProtKB
Endosome organization Source: UniProtKB
Endosome to lysosome transport Source: UniProtKB
Golgi organization Source: Ensembl
Lysosome organization Source: UniProtKB
Manchette assembly Source: Ensembl
Protein localization to perinuclear region of cytoplasm Source: UniProtKB
Protein transport Source: UniProtKB-KW

Cytoskeleton; Cytoplasm. Localizes to punctate cytoplasmic foci which do not appear to overlap with early or late endosomes, the endoplasmic reticulum, multivesicular bodies (MVBs), lysosomes, or mitochondria (By similarity). Often found in close association with microtubules (By similarity). Does not associate with the Golgi complex. During spermiogenesis, it localizes to the manchette in spermatids from steps 8-10. It is also present between the microtubule manchette and the nucleus. During manchette elongation, it is preferentially localized to the nuclear ring of the manchette, whereas the strong localization to the manchette decreases. In more mature spermatids, while the manchette migrates posteriorly, it localizes to punctuates spots. At later stages of spermatid differentiation, the punctuate expression pattern is found at both the attachment site and the proximal end of the elongated manchette. In contrast, it is not present in mature spermatozoa (By similarity).