| Structural highlights
Disease
[NMNA1_HUMAN] Defects in NMNAT1 are the cause of Leber congenital amaurosis 9 (LCA9) [MIM:608553]. A severe dystrophy of the retina, typically becoming evident in the first years of life. Visual function is usually poor and often accompanied by nystagmus, sluggish or near-absent pupillary responses, photophobia, high hyperopia and keratoconus.[1] [2] [3] [4]
Function
[NMNA1_HUMAN] Catalyzes the formation of NAD(+) from nicotinamide mononucleotide (NMN) and ATP. Can also use the deamidated form; nicotinic acid mononucleotide (NaMN) as substrate with the same efficiency. Can use triazofurin monophosphate (TrMP) as substrate. Also catalyzes the reverse reaction, i.e. the pyrophosphorolytic cleavage of NAD(+). For the pyrophosphorolytic activity, prefers NAD(+) and NAAD as substrates and degrades NADH, nicotinic acid adenine dinucleotide phosphate (NHD) and nicotinamide guanine dinucleotide (NGD) less effectively. Fails to cleave phosphorylated dinucleotides NADP(+), NADPH and NAADP(+). Protects against axonal degeneration following mechanical or toxic insults.[5]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Nicotinamide mononucleotide adenylyltransferase (NMNAT), a member of the nucleotidyltransferase alpha/beta-phosphodiesterases superfamily, catalyzes a universal step (NMN + ATP = NAD + PP(i)) in NAD biosynthesis. Localized within the nucleus, the activity of the human enzyme is greatly altered in tumor cells, rendering it a promising target for cancer chemotherapy. By using a combination of single isomorphous replacement and density modification techniques, the human NMNAT structure was solved by x-ray crystallography to a 2.5-A resolution, revealing a hexamer that is composed of alpha/beta-topology subunits. The active site topology of the enzyme, analyzed through homology modeling and structural comparison with other NMNATs, yielded convincing evidence for a substrate-induced conformational change. We also observed remarkable structural conservation in the ATP-recognition motifs GXXXPX(T/H)XXH and SXTXXR, which we take to be the universal signature for NMNATs. Structural comparison of human and prokaryotic NMNATs may also lead to the rational design of highly selective antimicrobial drugs.
Structure of human NMN adenylyltransferase. A key nuclear enzyme for NAD homeostasis.,Garavaglia S, D'Angelo I, Emanuelli M, Carnevali F, Pierella F, Magni G, Rizzi M J Biol Chem. 2002 Mar 8;277(10):8524-30. Epub 2001 Dec 19. PMID:11751893[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Koenekoop RK, Wang H, Majewski J, Wang X, Lopez I, Ren H, Chen Y, Li Y, Fishman GA, Genead M, Schwartzentruber J, Solanki N, Traboulsi EI, Cheng J, Logan CV, McKibbin M, Hayward BE, Parry DA, Johnson CA, Nageeb M, Poulter JA, Mohamed MD, Jafri H, Rashid Y, Taylor GR, Keser V, Mardon G, Xu H, Inglehearn CF, Fu Q, Toomes C, Chen R. Mutations in NMNAT1 cause Leber congenital amaurosis and identify a new disease pathway for retinal degeneration. Nat Genet. 2012 Sep;44(9):1035-9. doi: 10.1038/ng.2356. Epub 2012 Jul 29. PMID:22842230 doi:10.1038/ng.2356
- ↑ Chiang PW, Wang J, Chen Y, Fu Q, Zhong J, Chen Y, Yi X, Wu R, Gan H, Shi Y, Chen Y, Barnett C, Wheaton D, Day M, Sutherland J, Heon E, Weleber RG, Gabriel LA, Cong P, Chuang K, Ye S, Sallum JM, Qi M. Exome sequencing identifies NMNAT1 mutations as a cause of Leber congenital amaurosis. Nat Genet. 2012 Sep;44(9):972-4. doi: 10.1038/ng.2370. Epub 2012 Jul 29. PMID:22842231 doi:10.1038/ng.2370
- ↑ Perrault I, Hanein S, Zanlonghi X, Serre V, Nicouleau M, Defoort-Delhemmes S, Delphin N, Fares-Taie L, Gerber S, Xerri O, Edelson C, Goldenberg A, Duncombe A, Le Meur G, Hamel C, Silva E, Nitschke P, Calvas P, Munnich A, Roche O, Dollfus H, Kaplan J, Rozet JM. Mutations in NMNAT1 cause Leber congenital amaurosis with early-onset severe macular and optic atrophy. Nat Genet. 2012 Sep;44(9):975-7. doi: 10.1038/ng.2357. Epub 2012 Jul 29. PMID:22842229 doi:10.1038/ng.2357
- ↑ Falk MJ, Zhang Q, Nakamaru-Ogiso E, Kannabiran C, Fonseca-Kelly Z, Chakarova C, Audo I, Mackay DS, Zeitz C, Borman AD, Staniszewska M, Shukla R, Palavalli L, Mohand-Said S, Waseem NH, Jalali S, Perin JC, Place E, Ostrovsky J, Xiao R, Bhattacharya SS, Consugar M, Webster AR, Sahel JA, Moore AT, Berson EL, Liu Q, Gai X, Pierce EA. NMNAT1 mutations cause Leber congenital amaurosis. Nat Genet. 2012 Sep;44(9):1040-5. doi: 10.1038/ng.2361. Epub 2012 Jul 29. PMID:22842227 doi:10.1038/ng.2361
- ↑ Sorci L, Cimadamore F, Scotti S, Petrelli R, Cappellacci L, Franchetti P, Orsomando G, Magni G. Initial-rate kinetics of human NMN-adenylyltransferases: substrate and metal ion specificity, inhibition by products and multisubstrate analogues, and isozyme contributions to NAD+ biosynthesis. Biochemistry. 2007 Apr 24;46(16):4912-22. Epub 2007 Apr 3. PMID:17402747 doi:10.1021/bi6023379
- ↑ Garavaglia S, D'Angelo I, Emanuelli M, Carnevali F, Pierella F, Magni G, Rizzi M. Structure of human NMN adenylyltransferase. A key nuclear enzyme for NAD homeostasis. J Biol Chem. 2002 Mar 8;277(10):8524-30. Epub 2001 Dec 19. PMID:11751893 doi:10.1074/jbc.M111589200
|
