Gene Ontology annotation through association of InterPro records with GO terms
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Electronic Gene Ontology annotations created by ARBA machine learning models
Combined Automated Annotation using Multiple IEA Methods
A gene controlling variation in Arabidopsis glucosinolate composition is part of the methionine chain elongation pathway.
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Fine-mapping of GSL-ELONG identifies MAM1; missense mutants lack C4 glucosinolates; recombinant MAM1 condenses MTOB with acetyl-CoA.
"In cell-free enzyme assays, a heterologously expressed cDNA from this locus was capable of condensing 2-oxo-4-methylthiobutanoic acid with acetyl-coenzyme A, the initial reaction in Met chain elongation."
Biosynthesis of methionine-derived glucosinolates in Arabidopsis thaliana: recombinant expression and characterization of methylthioalkylmalate synthase, the condensing enzyme of the chain-elongation cycle.
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MAM1 catalyzes the condensing reactions of the first two elongation cycles only.
"Here we have demonstrated that MAM1, one of two similar genes in the A. thaliana ecotype Columbia, encodes a MAMS catalyzing the condensing reactions of the first two elongation cycles but not those of further cycles."
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MAM1 has no activity with IPMS or homocitrate synthase substrates; exclusively a secondary-metabolism enzyme.
"However, the MAM1 protein does not show activity with the substrates of any of these other enzymes, and was chromatographically separable from isopropylmalate synthase in extracts of A. thaliana."
Biochemical Genetics of Plant Secondary Metabolites in Arabidopsis thaliana: The Glucosinolates.
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gsm1 (TU1) mutant reduces aliphatic glucosinolates; GSM1 = MAM1.
"Mutants of Arabidopsis thaliana with a glucosinolate content different from wild type were isolated by screening a mutagenized population of plants."
Sorting signals, N-terminal modifications and abundance of the chloroplast proteome.
Water stress and aphid feeding differentially influence metabolite composition in Arabidopsis thaliana (L.).
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MAM1 transcripts up-regulated by drought and down-regulated by aphid feeding.
"Under drought stress, MAM1 and two transcription factors involved in aliphatic glucosinolate biosynthesis - MYB29 and MYB76 - were up-regulated two-fold"
Glucosinolate and amino acid biosynthesis in Arabidopsis.
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Of the four Col-0 MAM-like genes, only MAML-3 (an IPMS) complemented an IPMS-null E. coli; MAM1 did not.
"Only the expression of MAML-3 restored the ability of the mutant to grow in the absence of Leu."
MAM3 catalyzes the formation of all aliphatic glucosinolate chain lengths in Arabidopsis.
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mam1 mutants shift the profile from C4 to C3 glucosinolates; the paralog MAM3 is immunolocalized to chloroplasts.
"Plant lines with mutations in MAM1 showed a decrease in C 4 glucosinolates and a corresponding increase in C 3 glucosinolates."
Positive selection driving diversification in plant secondary metabolism.
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MAM1 acquired the ability to catalyze the second elongation cycle (biochemical neofunctionalization) after duplication from MAMa.
"Thus, Col-0 MAM1 controls the committed step in both the first and second round of methionine carbon chain elongation, ultimately leading to the formation of aliphatic glucosinolates with four methylene groups (4C) in their side chain."
Two Arabidopsis genes (IPMS1 and IPMS2) encode isopropylmalate synthase, the branchpoint step in the biosynthesis of leucine.
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IPMS1 and IPMS2, not MAM1, are the Arabidopsis isopropylmalate synthases of Leu biosynthesis.
"These enzymes catalyze the first dedicated step in leucine (Leu) biosynthesis, an aldol-type condensation of acetyl-coenzyme A (CoA) and 2-oxoisovalerate yielding isopropylmalate."