Genetic mapping and isolation of two arc3 alleles in Arabidopsis.
KEY MESSAGE                 :                                     Two new alleles of                    arc3                    in                   Arabidopsis thaliana,                    arc3-4                    and                   arc3-5, were isolated in the Columbia-0 ecotype. The mutants were characterized in detail using microscopy and molecular techniques.                                                                  Chloroplasts are essential organelles for photosynthesis in plant cells. Division of chloroplasts is coordinated by the internal division machinery (mainly the tubulin-like FtsZ ring) and the external division machinery (mainly the dynamin-like ARC5 ring). Accumulation and replication of chloroplasts3 (ARC3) is important for the correct positioning of chloroplast division machinery. During evolution, ARC3 has probably replaced minicellC (MinC), an important factor involved in positioning of the division site in bacteria. However, the working mechanism of ARC3 is still unclear. Using forward genetic approaches, we isolated two new alleles of arc3 in Arabidopsis thaliana, arc3-4 and arc3-5, in which mutant loci differed from those of previously reported arc3 mutants. Microscopy analyses showed more detailed, and some new, phenotypes of arc3 mutants. Reverse-transcription polymerase chain reaction (RT-PCR) and real-time quantitative RT-PCR (qRT-PCR) results indicated that the mRNA of the ARC3 gene was unstable in arc3-4 and arc3-5 mutant plants. Also, RNA secondary structures of the ARC3 gene were predicted to differ between these two arc3 mutants and wild type. Our studies increase our understanding of the function of ARC3 in chloroplast division.
College of Biological Sciences and Biotechnology, Beijing Forestry University, Haidian, Beijing, 100083, China.
Deng
D
Pan
Yuhong
Y
Shi
Xia
X
Liu
Yuefang
Y
Gao
Zhonghua
Z
Liu
Hongbo
H
Gao
D000483:Alleles; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002736:Chloroplasts / Q000378:metabolism; D002874:Chromosome Mapping; D020090:Chromosome Segregation / Q000235:genetics; D003433:Crosses, Genetic; D018506:Gene Expression Regulation, Plant; D005819:Genetic Markers; D058503:Mesophyll Cells / Q000166:cytology / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009690:Nucleic Acid Conformation; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
C493630:ARC3 protein, Arabidopsis; D029681:Arabidopsis Proteins; D005819:Genetic Markers; D012333:RNA, Messenger