There are several isoforms of MAT (MAT1aI/III) and MAT2a and there is a complicated switching mechanism back and forth for them depending on the nutritional status at any given moment. In low methionine/fasting conditions both BHMT and MAT1aI/III get up-regulated in the liver. MAT1a also up-regulates in the intestines in effort to capture any methionine making its way thru the GI tract. The activation of this portion of the methionine cycle during starvation may serve as a mechanism to preserve the SAM pool for methylation reactions and to hoard methionine during nutrient deprivation. Then, once fed, the switch flips and BHMT/MAT activity slows down in the liver and the methionine and amino acid pool can participate in other necessary pathways needed by the body (transsulfuration, biosynthesis of phospholipids, creatine, and polyamines).
Articles in this section
- Why Doesn’t StrateGene Report on APOE SNPs?
- My notable variation for a haplotype says "indeterminate" - what does this mean?
- How come the StrateGene SNP list is so different from what I am reading elsewhere online?
- How accurate are the COMT Haplotype speeds?
- How important is MAT1A in the SAM/methionine story?
- My COMT speed (specifically V158M/RS4680) was different in a previous StrateGene report than what is being reported here in my new StrateGene. Why is this?
- What does “increased risk” mean?
- How can I find more information about a particular SNP?
- I see results reported as NA, NC, or "indeterminate". What does this mean?
- What is meant by "tag SNP"?