Редактирование: NAT1 (раздел)

==Publications==

{{medline-entry
|title=Neonatal ontogeny of murine arylamine N-acetyltransferases: implications for arylamine genotoxicity.
|pubmed-url=https://pubmed.ncbi.nlm.nih.gov/12700401
|abstract=Age-related changes in the expression of xenobiotic biotransformation enzymes can result in differences in the rates of chemical activation and detoxification, affecting responses to the therapeutic and/or toxic effects of chemicals. Despite recognition that children and adults may exhibit differences in susceptibility to chemicals, information about when in development specific biotransformation enzymes are expressed is incomplete. N-acetyltransferases (NATs) are phase II enzymes that catalyze the acetylation of arylamine and hydrazine carcinogens and therapeutic drugs. The postnatal expression of [[NAT1]] and [[NAT2]] was investigated in C57Bl/6 mice. Hepatic [[NAT1]] and [[NAT2]] messenger RNAs (mRNAs) increased with age from neonatal day (ND) 4 to adult in a nonlinear fashion. The presence of functional proteins was confirmed by measuring NAT activities with the isoform selective substrates p-aminobenzoic acid and isoniazid, as well as the carcinogens 2-aminofluorene and 4-aminobiphenyl (4ABP). Neonatal liver was able to acetylate all of the substrates, with activities increasing with age. Protein expression of [[CYP1A2]], another enzyme involved in the biotransformation of arylamines, showed a similar pattern. The genotoxicity of 4ABP was assessed by determining hepatic 4ABP-DNA adducts. There was an age-dependent increase in 4ABP-DNA adducts during the neonatal period. Thus, developmental increases in expression of [[NAT1]] and [[NAT2]] genes in neonates are associated with less 4ABP genotoxicity. The age-related pattern of expression of biotransformation enzymes in mice is consistent with human data for NATs and suggests that this may play a role in developmental differences in arylamine toxicity.
|mesh-terms=* 4-Aminobenzoic Acid
* Acetyltransferases
* Aging
* Amino Acid Transport System A
* Amino Acid Transport Systems
* Aminobiphenyl Compounds
* Animals
* Animals, Newborn
* Arylamine N-Acetyltransferase
* Biotransformation
* Carrier Proteins
* Cytochrome P-450 CYP1A2
* DNA Adducts
* Fluorenes
* Isoenzymes
* Isoniazid
* Liver
* Mice
* Mice, Inbred C57BL
* Mutagens
* RNA, Messenger
* Reverse Transcriptase Polymerase Chain Reaction

|full-text-url=https://sci-hub.do/10.1093/toxsci/kfg086
}}
{{medline-entry
|title=The ontogeny of human drug-metabolizing enzymes: phase II conjugation enzymes and regulatory mechanisms.
|pubmed-url=https://pubmed.ncbi.nlm.nih.gov/11805192
|abstract=Changes in phase II drug-metabolizing enzyme expression during development, as well as the balance between phase I and phase II enzymes, can significantly alter the pharmacokinetics for a given drug or toxicant. Although our knowledge is incomplete, many of the phase II enzymes are expressed early in development. There is evidence for glutathione S-transferase A1/A2 (GSTA1/A2), GSTM, and [[GSTP1]] in fetal liver, lung and kidney, although tissue-specific patterns and changes with time are observed. N-Acetyltransferase 1 ([[NAT1]]) activity also has been reported throughout gestation in fetal liver, adrenal glands, lung, kidney, and intestine. Only postnatal changes in [[NAT1]] expression were apparent. Nothing is known about human [[NAT2]] developmental expression. Some UDP-glucuronosyltransferase and sulfotransferase isoforms also are detectable in fetal liver and other tissues by the first or second trimester, and substantial changes in isoform expression patterns, as well as overall expression levels, are observed with increasing maturity. Finally, expression of both epoxide hydrolases 1 and 2 (EPHX1 and EPHX2) is observed in fetal liver, and for the former, increased expression with time has been documented. Less is known about ontogenic molecular control mechanisms. Limited data suggest that the hepatocyte nuclear factor and CCAAT/enhancer binding protein families are critical for fetal liver drug-metabolizing enzyme expression whereas D element binding protein and related factors may regulate postnatal hepatic expression. There is a paucity of data regarding mechanisms for the onset of extrahepatic fetal expression or specific mechanisms determining temporal switches, such as those observed within the CYP3A and flavin-containing monooxygenase families.
|mesh-terms=* Acetyltransferases
* Aging
* Epoxide Hydrolases
* Gene Expression Regulation, Enzymologic
* Glucuronosyltransferase
* Glutathione Transferase
* Humans
* Pharmaceutical Preparations
* Sulfotransferases
* gamma-Glutamyl Hydrolase

|full-text-url=https://sci-hub.do/10.1124/jpet.300.2.361
}}
{{medline-entry
|title=Developmental regulation of the translational repressor [[NAT1]] during cardiac development.
|pubmed-url=https://pubmed.ncbi.nlm.nih.gov/10471355
|abstract=The process of translation initiation has been postulated to play an important role in the regulation of cellular growth and proliferation. Here, we report the identification and differential expression of a fundamental translational repressor [[NAT1]], during early postnatal cardiac development. Differential display analysis of RNA obtained from 3-day and 4-week-old rat hearts resulted in the cloning and identification of a 396 bp cDNA fragment (DRCF-6) which corresponded to the 3' terminal portion of [[NAT1]]. Northern blot analysis revealed that the mRNA expression of [[NAT1]] was markedly elevated during the first 2 weeks of postnatal life, with an apparent peak level of expression occurring at 1 week. [[NAT1]] mRNA levels then steadily decreased to 4 weeks of age. The [[NAT1]] transcript has previously been shown to be extensively edited by the enzyme APOBEC-1, which deaminates specific cytidine bases to uridine; cytidine deamination at a glutamine codon (CAA) results in the formation of a stop codon (UAA) and consequently, premature termination of translation. Accordingly, Western blot analysis detected the presence of several smaller proteins in addition to the full length [[NAT1]] protein (97 kDa), each exhibiting a distinct pattern of expression during cardiac development. APOBEC-1 editing of [[NAT1]] during cardiac development was further supported by primer extension analysis of cytidine 1699, which was found to be predominantly edited to uridine. Immunohistochemical staining showed that [[NAT1]] is expressed predominantly in atrial and ventricular myocytes, although staining was also detected in vascular smooth muscle cells and in the endocardium. These results suggest that [[NAT1]] may play a role in the postnatal development of the heart and demonstrate that APOBEC-1 editing may possibly be a novel mechanism by which translation is regulated during cardiac development.
|mesh-terms=* Aging
* Animals
* Arylamine N-Acetyltransferase
* Base Sequence
* DNA, Complementary
* Female
* Gene Expression Regulation, Developmental
* Heart
* Immunohistochemistry
* Isoenzymes
* Male
* Molecular Sequence Data
* Muscle Development
* Muscle, Smooth, Vascular
* Myocardium
* Pregnancy
* Rats
* Rats, Wistar

|full-text-url=https://sci-hub.do/10.1006/jmcc.1999.1008
}}
{{medline-entry
|title=Human acetylator genotype: relationship to colorectal cancer incidence and arylamine N-acetyltransferase expression in colon cytosol.
|pubmed-url=https://pubmed.ncbi.nlm.nih.gov/7902079
|abstract=Polymorphic expression of arylamine N-acetyltransferase (EC 2.3.1.5) may be a differential risk factor in metabolic activation of arylamine carcinogens and susceptibility to cancers related to arylamine exposures. Human epidemiological studies suggest that rapid acetylator phenotype may be associated with higher incidences of colorectal cancer. We used restriction fragment length polymorphism analysis to determine acetylator genotypes of 44 subjects with colorectal cancer and 28 non-cancer subjects of similar ethnic background (i.e., approximately 25% Black and 75% White). The polymorphic N-acetyltransferase gene ([[NAT2]]) was amplified by the polymerase chain reaction from DNA templates derived from human colons of colorectal and non-cancer subjects. No significant differences in [[NAT2]] allelic frequencies (i.e., WT, M1, M2, M3 alleles) or in acetylator genotypes were found between the colorectal cancer and non-cancer groups. No significant differences in [[NAT2]] allelic frequencies were observed between Whites and Blacks or between males and females. Cytosolic preparations from the human colons were tested for expression of arylamine N-acetyltransferase activity. Although N-acetyltransferase activity was expressed for each of the arylamines tested (i. e., p-aminobenzoic acid, 4-aminobiphenyl, 2-aminofluorene, beta-naphthylamine), no correlation was observed between acetylator genotype and expression of human colon arylamine N-acetyltransferase activity. Similarly, no correlation was observed between subject age and expression of human colon arylamine N-acetyltransferase activity. These results suggest that arylamine N-acetyltransferase activity expressed in human colon is catalyzed predominantly by [[NAT1]], an arylamine N-acetyltransferase that is not regulated by [[NAT2]] acetylator genotype.(ABSTRACT TRUNCATED AT 250 WORDS)
|mesh-terms=* Acetylation
* Aging
* Alleles
* Arylamine N-Acetyltransferase
* Base Sequence
* Colon
* Colorectal Neoplasms
* Cytosol
* Female
* Gene Frequency
* Genotype
* Humans
* Incidence
* Male
* Middle Aged
* Molecular Sequence Data
* Polymerase Chain Reaction
* Polymorphism, Restriction Fragment Length
* Risk Factors

|full-text-url=https://sci-hub.do/10.1007/BF01969914
}}