Defective ABCB6 does not transport porphyrin from cytosol into mitochondria matrix

Stable Identifier
Reaction [transition]
Homo sapiens
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ATP-binding cassette sub-family B member 6 (ABCB6), uniquely located on the outer mitochondrial membrane in homodimeric form, plays a crucial role in haem synthesis by mediating porphyrin uptake into the mitochondria. Defects in ABCB6 can cause isolated colobomatous microphthalmia 7 (MCOPCB7; MIM:614497), a developmental defect of the eye resulting from abnormal or incomplete fusion of the optic fissure with associated microphthalmia (eyeballs are abnormally small). Coloboma is thought to play an important role in the early development of the CNS, including that of the eye. Mutations causing MCOPCB7 are L811V and A57T (Wang et al. 2012).

Literature References
PubMed ID Title Journal Year
22226084 ABCB6 mutations cause ocular coloboma

Namburi, P, Du, W, Yang, Z, Li, W, Wang, L, Li, DY, Gong, B, He, F, Bu, J, Jia, Y, Soltis, KA, Cooney, JD, Dong, J, Liu, X, Li, J, Phillips, JD, Shi, Y, Sundaresan, P, Lu, F, Paw, BH, Liang, C, McBride, PF, Lin, Y, Wang, L, Zhen, Y, Dubey, SK, Liu, X

Am. J. Hum. Genet. 2012
Catalyst Activity

ABC-type heme transporter activity of ABCB6 mutants [mitochondrial outer membrane]

Normal reaction
Functional status

Loss of function of ABCB6 mutants [mitochondrial outer membrane]

Name Identifier Synonyms
microphthalmia DOID:10629 simple microphthalmos, nanophthalmia, microphthalmos, nanophthalmos
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