title: Identification of Mga1, a G-protein alpha-subunit gene involved in regulating citrinin and pigment production in Monascus ruber M7.
abstract: The filamentous fungi Monascus spp., which have been used in traditional fermented food in Asia for centuries, are well-known producers of a group of bioactive metabolites that are widely used as food additives and nutraceutical supplements worldwide. However, its potential to produce the mycotoxin citrinin poses a threat to food safety. Here, a G-protein alpha-subunit-encoding gene, Mga1 (Monascus G-protein alpha-subunit 1), which encodes a protein showing a high degree of identity to Group I alpha-subunits of fungal heterotrimeric G-proteins, was cloned from Monascus ruber M7. An Mga1-disrupted strain was obtained by homologous recombination. The disruptant produced approximately nine times more citrinin and 71% more pigments than the wild-type strain M7, indicating that the G-protein alpha-subunit encoded by Mga1 is involved in a signal transduction pathway regulating citrinin and pigment biosynthesis in M. ruber M7.
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Hubei Province, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Yanchun
authors.initials: Y
authors.lastname: Shao
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.forename: Sha
authors.initials: S
authors.lastname: Yang
authors.forename: Fusheng
authors.initials: F
authors.lastname: Chen
mesh_terms: D002953:Citrinin / Q000096:biosynthesis*; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D005656:Fungal Proteins / Q000378:metabolism*; D044385:GTP-Binding Protein alpha Subunits / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D055786:Gene Knockout Techniques; D008969:Molecular Sequence Data; D032741:Monascus / Q000502:physiology*; D010860:Pigments, Biological / Q000096:biosynthesis*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D044385:GTP-Binding Protein alpha Subunits; D010860:Pigments, Biological; D002953:Citrinin