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Author Shi, Dong-Qiao ♦ Liu, Jie ♦ Xiang, Yan-Hui ♦ Ye, De ♦ Sundaresan, Venkatesan ♦ Yang, Wei-Cai
Source World Health Organization (WHO)-Global Index Medicus
Content type Text
Publisher American Society of Plant Biologists
File Format HTM / HTML
Language English
Difficulty Level Medium
Subject Domain (in DDC) Computer science, information & general works ♦ Library & information sciences ♦ Natural sciences & mathematics ♦ Chemistry & allied sciences ♦ Life sciences; biology ♦ Physiology & related subjects ♦ Biochemistry ♦ Genetics and evolution ♦ Natural history of organisms ♦ Technology ♦ Medicine & health ♦ Human physiology ♦ Pharmacology and therapeutics ♦ Diseases ♦ Manufacture for specific uses ♦ Precision instruments & other devices
Subject Domain (in MeSH) Eukaryota ♦ Organisms ♦ Amino Acids, Peptides, and Proteins ♦ Nucleic Acids, Nucleotides, and Nucleosides ♦ Chemicals and Drugs ♦ Investigative Techniques ♦ Analytical, Diagnostic and Therapeutic Techniques and Equipment ♦ Chemical Phenomena ♦ Genetic Phenomena ♦ Biological Sciences ♦ Information Science ♦ Information Science
Subject Keyword Discipline Botany ♦ Arabidopsis Proteins ♦ Genetics ♦ Arabidopsis ♦ Cell Cycle Proteins ♦ Rna, Ribosomal, 18s ♦ Amino Acid Sequence ♦ Growth & Development ♦ Conserved Sequence ♦ Gene Expression Regulation, Plant ♦ Molecular Sequence Data ♦ Rna, Plant ♦ Biosynthesis ♦ Sequence Alignment ♦ Sequence Homology, Amino Acid ♦ Journal Article ♦ Research Support, Non-u.s. Gov't
Abstract The progression of mitotic division cycles and synchronous development between and within the male and female reproductive organs are essential for plant sexual reproduction. Little is known about the genetic control of the progression of mitotic cycles of the haploid genome during gametogenesis in higher plants. Here, we report the phenotypic and molecular characterization of an Arabidopsis thaliana mutant, slow walker1 (swa1), in which the progression of the mitotic division cycles of the female gametophyte was disrupted. Confocal microscopy revealed that megagametophyte development was asynchronous in swa1, causing embryo sacs to arrest at two-, four-, or eight-nucleate stages within the same pistil. A delayed pollination experiment showed that a small fraction of the swa1 embryo sacs were able to develop into functional female gametophytes. The swa1 mutation also showed a slight reduction in penetrance through the male gametophyte, although the pollen grains were morphologically normal. Molecular analysis indicates that SWA1 encodes a protein with six WD40 repeats that is localized in the nucleolus in interphase cells. The SWA1 gene is expressed in cells undergoing active cell divisions, including functional megaspores and the female gametophytic cells. RNA interference results indicated that knockout of SWA1 inhibited root growth significantly and led to the accumulation of unprocessed 18S pre-rRNA. These data suggest that SWA1 most likely plays a role in rRNA biogenesis that is essential for the progression of the mitotic division cycles during gametogenesis in plants.
Description Country affiliation: China
Author Affiliation: Shi DQ ( Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.)
ISSN 10404651
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Reading ♦ Research ♦ Self Learning
Interactivity Type Expositive
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2005-08-01
Publisher Place United States
e-ISSN 1531298X
Volume Number 17
Issue Number 8

Source: WHO-Global Index Medicus