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.
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.
Lin-Chuan
LC
Li
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.
Gen-Ji
GJ
Qin
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Tomohiko
T
Tsuge
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.
Xian-Hui
XH
Hou
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.
Mao-Yu
MY
Ding
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Takashi
T
Aoyama
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Atsuhiro
A
Oka
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.
Zhangliang
Z
Chen
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.
Hongya
H
Gu
Section of Cell and Developmental Biology, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
Yunde
Y
Zhao
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.
Li-Jia
LJ
Qu
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