Trimethyllysine dioxygenase, mitochondrial is an enzyme that in humans is encoded by the TMLHEgene in chromosome X.[4][5][6] Mutations in the TMLHE gene resulting in carnitine biosynthesis disruption have been associated with autism symptoms.[7]
Structure
The TMHLE gene is located at the extreme end of the Xq28 region with high genomic instability,[8] and encodes a protein trimethyllysine dioxygenase, a, Fe2+ and 2-oxoglytarate dependent non-heme-ferrous iron hydrolase localized to the mitochondrial matrix.[9]
Function
The trimethyllysine dioxygenase enzyme catalyzes the first step in the carnitine biosynthesis pathway,[9] which is part of amine biosynthesis. Carnitine is a molecule that play an essential role in the transport of activated fatty acids across the inner mitochondrial membrane where they are metabolized. The encoded protein converts trimethyllysine into hydroxytrimethyllysine with the reaction (EC 1.14.11.8):
^ abZiats MN, Comeaux MS, Yang Y, Scaglia F, Elsea SH, Sun Q, Beaudet AL, Schaaf CP (September 2015). "Improvement of regressive autism symptoms in a child with TMLHE deficiency following carnitine supplementation". American Journal of Medical Genetics. Part A. 167A (9): 2162–7. doi:10.1002/ajmg.a.37144. PMID25943046. S2CID205320608.
^Monfregola J, Napolitano G, Conte I, Cevenini A, Migliaccio C, D'Urso M, Ursini MV (2007). "Functional characterization of the TMLH gene: promoter analysis, in situ hybridization, identification and mapping of alternative splicing variants". Gene. 395 (1–2): 86–97. doi:10.1016/j.gene.2007.02.012. PMID17408883.
^ abMonfregola J, Cevenini A, Terracciano A, van Vlies N, Arbucci S, Wanders RJ, D'Urso M, Vaz FM, Ursini MV (2005). "Functional analysis of TMLH variants and definition of domains required for catalytic activity and mitochondrial targeting". J. Cell. Physiol. 204 (3): 839–47. doi:10.1002/jcp.20332. PMID15754339. S2CID25224767.
Monfregola J, Cevenini A, Terracciano A, van Vlies N, Arbucci S, Wanders RJ, D'Urso M, Vaz FM, Ursini MV (September 2005). "Functional analysis of TMLH variants and definition of domains required for catalytic activity and mitochondrial targeting". Journal of Cellular Physiology. 204 (3): 839–47. doi:10.1002/jcp.20332. PMID15754339. S2CID25224767.
Mehrle A, Rosenfelder H, Schupp I, del Val C, Arlt D, Hahne F, Bechtel S, Simpson J, Hofmann O, Hide W, Glatting KH, Huber W, Pepperkok R, Poustka A, Wiemann S (January 2006). "The LIFEdb database in 2006". Nucleic Acids Research. 34 (Database issue): D415-8. doi:10.1093/nar/gkj139. PMC1347501. PMID16381901.
Monfregola J, Napolitano G, Conte I, Cevenini A, Migliaccio C, D'Urso M, Ursini MV (June 2007). "Functional characterization of the TMLH gene: promoter analysis, in situ hybridization, identification and mapping of alternative splicing variants". Gene. 395 (1–2): 86–97. doi:10.1016/j.gene.2007.02.012. PMID17408883.