Alternative splicing of the auxin biosynthesis gene YUCCA4 determines its subcellular compartmentation.
Auxin is a major growth hormone in plants, and recent studies have elucidated many of the molecular mechanisms underlying its action, including transport, perception and signal transduction. However, major gaps remain in our knowledge of auxin biosynthetic control, partly due to the complexity and probable redundancy of multiple pathways that involve the YUCCA family of flavin-dependent mono-oxygenases. This study reveals the differential localization of YUCCA4 alternative splice variants to the endoplasmic reticulum and the cytosol, which depends on tissue-specific splicing. One isoform is restricted to flowers, and is anchored to the cytosolic face of the endoplasmic reticulum membrane via a hydrophobic C-terminal transmembrane domain. The other isoform is present in all tissues and is distributed throughout the cytosol. These findings are consistent with previous observations of yucca4 phenotypes in flowers, and suggest a role for intracellular compartmentation in auxin biosynthesis.
Biomedical Research Centre, Sheffield Hallam University, Sheffield S1 1WB, UK. v.kriechbaumer@shu.ac.uk
Verena
V
Kriechbaumer
Pengwei
P
Wang
Chris
C
Hawes
Ben M
BM
Abell
D017398:Alternative Splicing; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D006899:Mixed Function Oxygenases / Q000235:genetics* / Q000378:metabolism; D010105:Oxygenases / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D007527:Isoenzymes; D008164:Luminescent Proteins; D006899:Mixed Function Oxygenases; C574208:YUCCA4 protein, Arabidopsis; D010105:Oxygenases; C422746:YUC protein, Arabidopsis