LMBRD1 transports lysosomal Cbl to cytosol

Stable Identifier
Reaction [transition]
Homo sapiens
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The probable lysosomal cobalamin transporter (LMBD1) is the most likely candidate to transport cobalamin (Cbl) from inside the lysosome to the cytosol (Rutsch et al. 2009). From here, Cbl can either be used to synthesise the essential cofactors for methionine synthase in the cytosol or methylmalonyl-CoA mutase in the mitochondria or, it can transported out of the cell to tissues that require Cbl. Defects in LMBRD1 (the gene that produces LMBD1) cause methylmalonic aciduria and homocystinuria type cblF (MMAHCF; MIM:277380), characterised biochemically by decreased levels of the coenzymes adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl) (Rutsch et al. 2009, Gailus et al. 2010).

Literature References
PubMed ID Title Journal Year
20174775 Insights into lysosomal cobalamin trafficking: lessons learned from cblF disease

Gailus, S, Höhne, W, Gasnier, B, Nürnberg, P, Fowler, B, Rutsch, F

J. Mol. Med. 2010
19136951 Identification of a putative lysosomal cobalamin exporter altered in the cblF defect of vitamin B12 metabolism

Rutsch, F, Gailus, S, Miousse, IR, Suormala, T, Sagné, C, Toliat, MR, Nürnberg, G, Wittkampf, T, Buers, I, Sharifi, A, Stucki, M, Becker, C, Baumgartner, M, Robenek, H, Marquardt, T, Höhne, W, Gasnier, B, Rosenblatt, DS, Fowler, B, Nürnberg, P

Nat. Genet. 2009
Participant Of
Catalyst Activity
Catalyst Activity
ATPase-coupled vitamin B12 transmembrane transporter activity of LMBRD1 [lysosomal membrane]
Physical Entity
Orthologous Events
Cross References
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