Haem regulation of the mitochondrial import of the Kluyveromyces lactis 5-aminolaevulinate synthase: an organelle approach.
The enzyme 5-aminolaevulinate acid synthase (ALAS) catalyses the first reaction in the haem biosynthetic pathway. In eukaryotes this protein is translated by cytosolic ribosomes and then targeted to the mitochondria. We present evidence that in the yeast Kluyveromyces lactis haem exerts a feedback control upon the import of the ALAS into mitochondria. The ALAS from K. lactis (KlALAS) contains two haem regulatory motifs (HRM) in the mitochondrial targeting signal. Mutagenesis experiments reveal the involvement of these HRM in the response of the KlALAS to haem.
González-Domínguez
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Departamento Biología Celular y Molecular, Universidad de A Coruña, F. Ciencias, Campus de A Zapateira, s/n 15075, A Coruña, Spain.
Freire-Picos
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MA
Cerdán
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ME
D000624:5-Aminolevulinate Synthetase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001483:Base Sequence; D004792:Enzyme Precursors / Q000378:metabolism; D005246:Feedback; D006418:Heme / Q000378:metabolism*; D006427:Hemin / Q000494:pharmacology*; D007716:Kluyveromyces / Q000201:enzymology* / Q000235:genetics; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D021382:Protein Sorting Signals; D021381:Protein Transport / Q000187:drug effects; D011993:Recombinant Fusion Proteins / Q000378:metabolism
D004792:Enzyme Precursors; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; D006418:Heme; D006427:Hemin; D000624:5-Aminolevulinate Synthetase