Os03g0843600
Os-CASTOR was identified as Os03g62650 in the rice genome (Nipponbare) based on The Institute for Genomic Research Rice Genome Annotation.
Contents
Annotated Information
Function
- Os-CASTOR and Os-POLLUX are indispensable for mycorrhizal symbiosis in rice. The knockout of Os-CASTOR and Os-POLLUX has completely abolished the ability of the AM fungus to enter the plant root.
Mutation
- The researchers identified one T-DNA insertion allele for Os-CASTOR in the genetic background of the japonica rice cv Hawyoung (line no. C04353), hereafter referred to as Os-castor-1. In the Os-castor-1 mutant, the T-DNA was inserted into the second 72-bp exon[1].
- To test whether Os-CASTOR and Os-POLLUX are required for AM symbiosis in rice, we inoculated the mutant and wild-type rice roots with the fungus Glomus intraradices. At 35 d after inoculation, wildtype plants were densely colonized by G. intraradices, exhibiting the range of symbiotic structures typical of a functional symbiosis, including intercellular and intracellular hyphae, vesicles, and arbuscules. In each of the 60 wild-type plants from the genotypes Nipponbare, Hawyoung, and Dongjin, approximately 60% to 85% of the total root length was colonized. Similar levels of colonization also were observed for wild-type plants segregated from heterozygous mutant plants (Fig. 4). In contrast, intracellular fungal structures, including vesicles and arbuscules, were not observed on roots of 60 Os-castor-1, 72 Os-pollux-1, and 60 Ospollux- 2 homozygous mutant plants. For homozygous mutant plants, extraradical hyphae and appressoria were frequently observed on the root surface (Fig. 4), but the fungus was unable to penetrate the roots beyond the epidermis. These observations indicate that the knockout of Os-CASTOR and Os-POLLUX has completely abolished the ability of the AM fungus to enter the plant root[1].
Figure 4. Os-castor and Os-pollux are defective in AM symbiosis. A to C, Roots of wild-type plants segregated from heterozygous mutants formed arbuscules upon inoculation with G. intraradices. D to F, Roots of homozygous mutants failed to form AM symbiosis, despite the presence of fungal hyphae on the root surface. Photographs were taken from roots at 5 weeks after inoculation with G. intraradices. Mycorrhizal colonization was assessed by trypan blue staining according to the procedures described by Koske and Gemma (1989). Stained roots were examined using a light microscope (Olympus BX40F-3), and images were captured by a microscope digital camera system (Olympus DP71). ap, Appressorium; ar, arbuscule; eh, extraradical hypha; ih, intraradical hypha. [1].
Expression
Please input expression information here.
Evolution
- The between-species orthologous relationship of the CASTOR-POLLUX homologs can be readily inferred based on phylogenetic analysis (Fig. 1) and their microsyntenic genomic position[2].
Figure 1. Phylogenetic tree (unrooted) of CASTOR and POLLUX homologs in M. truncatula (Mt), L. japonicus (Lj), soybean (Gm), poplar (Pt), grapevine (Vv), Arabidopsis (At), rice (Os), sorghum (Sb), and maize (Zm). [2].
Labs working on this gene
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546 Root
References
- ↑ 1.0 1.1 1.2 Chen C, Fan C, Gao M, Zhu H. Antiquity and function of CASTOR and POLLUX, the twin ion channel-encoding genes key to the evolution of root symbioses in plants. Plant Physiol. 2009 Jan;149(1):306-17. doi: 10.1104/pp.108.131540. Epub 2008 Oct 31. PubMed PMID: 18978069; PubMed Central PMCID: PMC2613720.
- ↑ 2.0 2.1 ZhuH, Riely BK, BurnsNJ, Ane JM(2006) Tracing nonlegume orthologs of legume genes required for nodulation and arbuscular mycorrhizal symbioses. Genetics 172: 2491–2499
