SPOROCYTELESS modulates YUCCA expression to regulate the development of lateral organs in Arabidopsis.
* Auxin is essential for many aspects of plant growth and development, including the determination of lateral organ shapes. * Here, the characterization of a dominant Arabidopsis thaliana mutant spl-D (SPOROCYTELESS dominant), and the roles of SPL in auxin homeostasis and plant development, are reported. * The spl-D mutant displayed a severe up-curling leaf phenotype caused by increased expression of SPOROCYTELESS/NOZZLE (SPL/NZZ), a putative transcription factor gene that was previously linked to sporocyte formation. The spl-D plants also displayed pleiotropic developmental defects including fewer lateral roots, simpler venation patterns, and reduced shoot apical dominance. The leaf and floral phenotypes of spl-D and SPL over-expression lines were reminiscent of yucca (yuc) triple and quadruple mutants, suggesting that SPL may regulate auxin homeostasis. Consistent with this hypothesis, it was found that over-expression of SPL led to down-regulation of the auxin reporter DR5-GUS, and that many auxin-responsive genes were down-regulated in spl-D leaves. Interestingly, the expression of YUC2 and YUC6, two key genes in auxin biosynthesis, was significantly repressed in spl-D plants. * Taken together with the genetic and phenotypic analysis of spl-D/yuc6-D double mutant, these data suggest that SPL may regulate auxin homeostasis by repressing the transcription of YUC2 and YUC6 and participate in lateral organ morphogenesis.
Li
Lin-Chuan
LC
National Laboratory for Protein Engineering and Plant Genetic Engineering, Peking-Yale Joint Research Center for Plant Molecular Genetics and AgroBiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.
Qin
Gen-Ji
GJ
National Laboratory for Protein Engineering and Plant Genetic Engineering, Peking-Yale Joint Research Center for Plant Molecular Genetics and AgroBiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.
Tsuge
Tomohiko
T
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Hou
Xian-Hui
XH
National Laboratory for Protein Engineering and Plant Genetic Engineering, Peking-Yale Joint Research Center for Plant Molecular Genetics and AgroBiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.
Ding
Mao-Yu
MY
National Laboratory for Protein Engineering and Plant Genetic Engineering, Peking-Yale Joint Research Center for Plant Molecular Genetics and AgroBiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.
Aoyama
Takashi
T
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Oka
Atsuhiro
A
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Chen
Zhangliang
Z
National Laboratory for Protein Engineering and Plant Genetic Engineering, Peking-Yale Joint Research Center for Plant Molecular Genetics and AgroBiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.
Gu
Hongya
H
National Laboratory for Protein Engineering and Plant Genetic Engineering, Peking-Yale Joint Research Center for Plant Molecular Genetics and AgroBiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.|The National Plant Gene Research Center (Beijing), Beijing 100101, China.
Zhao
Yunde
Y
Section of Cell and Developmental Biology, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
Qu
Li-Jia
LJ
National Laboratory for Protein Engineering and Plant Genetic Engineering, Peking-Yale Joint Research Center for Plant Molecular Genetics and AgroBiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.|The National Plant Gene Research Center (Beijing), Beijing 100101, China.
D017360:Arabidopsis / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology*; D003001:Cloning, Molecular; D018506:Gene Expression Regulation, Plant; D006706:Homeostasis; D007210:Indoleacetic Acids / Q000378:metabolism; D016254:Mutagenesis, Insertional; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D010105:Oxygenases / Q000096:biosynthesis / Q000235:genetics*; D010641:Phenotype; D018515:Plant Leaves / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified / Q000254:growth & development / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology*
D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D009687:Nuclear Proteins; D012097:Repressor Proteins; C416221:SPL protein, Arabidopsis; D010105:Oxygenases; C422746:YUC protein, Arabidopsis