Os03g0323200 - Revision history

Liman at 11:23, 1 August 2016

2016-08-01T11:23:27Z

Liman at 11:14, 1 August 2016

2016-08-01T11:14:29Z

Liman at 11:14, 1 August 2016

2016-08-01T11:14:12Z

Liman: /* Function */

2016-08-01T11:11:16Z

‎Function

Liman: /* Function */

2016-08-01T11:08:50Z

‎Function

Liman at 11:05, 1 August 2016

2016-08-01T11:05:51Z

Liman at 10:56, 1 August 2016

2016-08-01T10:56:31Z

Liman at 09:32, 1 August 2016

2016-08-01T09:32:12Z

Liman: /* References */

2016-08-01T09:27:52Z

‎References

Liman: /* Mutation */

2016-08-01T09:27:36Z

‎Mutation

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 Yamazaki, J., Kamimura, Y., Okada, M. and Sugimura, Y. (1999) Changes in photosynthetic characteristics and photosystem stoichiometries in the lower leaves in rice seedlings. Plant Sci. 148: 155–163.
 </ref>
 </references>
 ==Structured Information==
       [[Category:Genes]][[Category:Oryza Sativa Japonica Group]][[Category:Japonica Chromosome 3]]

← Older revision		Revision as of 11:14, 1 August 2016
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−	* The rice gene Os03g0323200 was reported as '''''OsCHLH''''' in 2003<ref name="ref1" />. The '''''OsCHLH ~~gene~~''''' could encode a protein of 1,388 amino acids with a putative N-terminal chloroplast transit peptide.	+	* The rice gene Os03g0323200 was reported as '''''OsCHLH''''' in 2003<ref name="ref1" />. The '''''OsCHLH''''' gene could encode a protein of 1,388 amino acids with a putative N-terminal chloroplast transit peptide.

	==Annotated Information==		==Annotated Information==

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 ==Annotated Information==
 ===Function===
-* The '''''OsCHLH''''' gene encodes the largest subunit of the rice Mg-chelatase, a key enzyme in the chlorophyll branch of the tetrapyrrole biosynthetic pathway.
+* The '''''OsCHLH''''' gene encodes the largest subunit of the rice Mg-chelatase, a key enzyme in the chlorophyll branch of the tetrapyrrole biosynthetic pathway<ref name="ref1" />.
-* Transcript levels of the '''''OsCHLH''''' gene are increased by light. The researchers also found this induction by assaying the fusion product between '''''OsCHLH''''' and GUS.
+* Transcript levels of the '''''OsCHLH''''' gene are increased by light. The researchers also found this induction by assaying the fusion product between '''''OsCHLH''''' and GUS<ref name="ref1" />.
-* The '''''OsCHLH''''' gene is essential for rice plants. Knockout mutations of this gene result in a seedling-lethal phenotype. DNA gel-blot analysis of rice genomic DNA indicates only a single copy of the gene.
+* The '''''OsCHLH''''' gene is essential for rice plants. Knockout mutations of this gene result in a seedling-lethal phenotype. DNA gel-blot analysis of rice genomic DNA indicates only a single copy of the gene<ref name="ref1" />.
-* The researchers suggest that the C-terminal region is essential for CHLH enzyme activity. Based on the RGP mapping data, '''''OsCHLH''''' is positioned near the chl2 locus on Chromosome 3.
+* The researchers suggest that the C-terminal region is essential for CHLH enzyme activity. Based on the RGP mapping data, '''''OsCHLH''''' is positioned near the chl2 locus on Chromosome 3<ref name="ref1" />.
 ===Mutation===
-* Light microscopic observation of the cross-section of the chlorina mutant leaf blade did not show any significant change in the size or number of mesophyll cells (data not known). However, TEM analysis revealed that, although there was no change in the number of chloroplasts, their shape in the OschlH mutant was irregular compared with the wild-type chloroplasts (Fig. 1). The knockout mutant did not show dispersal of prolamella bodies and retained the appearance of an etioplast in the continuous light condition. Thylakoid membranes in the mutant chloroplasts also were severely disrupted. The reduction of light harvesting complexes in the thylakoid membrane due to the lack of chlorophyll synthesis may disrupt the thylakoid ultrastructure in the mutant.
+* Light microscopic observation of the cross-section of the chlorina mutant leaf blade did not show any significant change in the size or number of mesophyll cells (data not known). However, TEM analysis revealed that, although there was no change in the number of chloroplasts, their shape in the OschlH mutant was irregular compared with the wild-type chloroplasts (Fig. 1). The knockout mutant did not show dispersal of prolamella bodies and retained the appearance of an etioplast in the continuous light condition. Thylakoid membranes in the mutant chloroplasts also were severely disrupted. The reduction of light harvesting complexes in the thylakoid membrane due to the lack of chlorophyll synthesis may disrupt the thylakoid ultrastructure in the mutant<ref name="ref1" />.
 [[File:Os03g0323200-1.png|center|thumb|400px|'''Fig. 1 TEM analysis of the OschlH mutant and wild-type chloroplasts. (A), (C), and (E) are sections of OschlH mutant chloroplasts; (B), (D), and (F) are sections of wild-type chloroplasts. Scale bars = 1 μm; open arrow, thylakoid membrane; filled arrow, prolamellar body; Cp, chloroplast.''' '' <ref name="ref1" />.'']]
-* The researchers measured chlorophyll contents in 10-day-old seedlings (Table 1). In wild-type and the heterozygotic plants, the ratio between chlorophyll a and chlorophyll b was about three <ref name="ref2" />. However, in homozygotic plants, the levels of chlorophylls were very low, indicating lack of chlorophyll biosynthesis.
+* The researchers measured chlorophyll contents in 10-day-old seedlings (Table 1). In wild-type and the heterozygotic plants, the ratio between chlorophyll a and chlorophyll b was about three <ref name="ref2" />. However, in homozygotic plants, the levels of chlorophylls were very low, indicating lack of chlorophyll biosynthesis<ref name="ref1" />.
 [[File:Os03g0323200-2.png|center|thumb|400px|'''Table 1 Chlorophyll contents of wild-type, heterozygous, and homozygous plants''' '' <ref name="ref1" />.'']]
 ===Expression Pattern===
-* Gus assays were conducted in seedlings of the T3 heterozygotic plants that were grown under either continuous light or in the dark. GUS-activity was light inducible in the coleoptiles, leaves, and roots of the light-grown seedlings (Fig. 2A, B). Dark-grown seedlings showed a low level of GUS activity, primarily in the scutellum tissue, indicating that a basal level of the OsCHLH transcript still exists under darkness. The crosssection of the light-grown seedlings showed that GUS activity was prominent in the cortical tissues of the roots (Fig. 2C) and in the mesophyll cells of the coleoptiles (Fig. 2D). In the immature flower, GUS activity was observed primarily in the palea/lemma, while in the mature flower, the fusion gene was expressed strongly in the palea/lemma and weakly in the ovary (Fig. 2E, F). In the leaves of 15-day-old seedlings, expression was confined to the mesophyll cells (Fig. 2G).
+* Gus assays were conducted in seedlings of the T3 heterozygotic plants that were grown under either continuous light or in the dark. GUS-activity was light inducible in the coleoptiles, leaves, and roots of the light-grown seedlings (Fig. 2A, B). Dark-grown seedlings showed a low level of GUS activity, primarily in the scutellum tissue, indicating that a basal level of the OsCHLH transcript still exists under darkness. The crosssection of the light-grown seedlings showed that GUS activity was prominent in the cortical tissues of the roots (Fig. 2C) and in the mesophyll cells of the coleoptiles (Fig. 2D). In the immature flower, GUS activity was observed primarily in the palea/lemma, while in the mature flower, the fusion gene was expressed strongly in the palea/lemma and weakly in the ovary (Fig. 2E, F). In the leaves of 15-day-old seedlings, expression was confined to the mesophyll cells (Fig. 2G)<ref name="ref1" />.
 [[File:Os03g0323200-3.png|center|thumb|400px|'''Fig. 2 Analysis of the tagged-gene expression patterns using GUS
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 ===Evolution===
 * The OsCHLH gene could encode a protein of 1,388 amino acids with a putative N-terminal chloroplast transit peptide
-(Fig. 3). A calculated molecular mass of 154 kDa corresponds to the size of the homologous precursor CHLH protein from higher plants (Hudson et al. 1993, Gibson et al. 1996, Jensen et al. 1996). Compared with other CHLH sequences, the OsCHLH protein has 88% identity with the barley XANTHA-F subunit, 84% with the soybean CHLH, 82% with the garden snapdragon CHLH, 81% with the tobacco CHLH, and 81% with the Arabidopsis thaliana CHLH. Although the N-terminal regions (1st to ~49th residues) of CHLHs are variable, the remaining regions are highly conserved (Fig. 3).
+(Fig. 3). A calculated molecular mass of 154 kDa corresponds to the size of the homologous precursor CHLH protein from higher plants (Hudson et al. 1993, Gibson et al. 1996, Jensen et al. 1996). Compared with other CHLH sequences, the OsCHLH protein has 88% identity with the barley XANTHA-F subunit, 84% with the soybean '''''CHLH''''', 82% with the garden snapdragon CHLH, 81% with the tobacco CHLH, and 81% with the Arabidopsis thaliana CHLH. Although the N-terminal regions (1st to ~49th residues) of '''''CHLHs''''' are variable, the remaining regions are highly conserved (Fig. 3)<ref name="ref1" />.
-[[File:Os03g0323200-4.png|center|thumb|400px|'''Fig. 3 Predicted amino acid sequence of OsCHLH. The sequence was multiple-aligned with Arabidopsis CHLH (Z68495), soybean CHLH (AJ001091), tobacco CHLH (AF014052), and barley XANTHAF (U26916).''' '' <ref name="ref1" />.'']]
+[[File:Os03g0323200-4.png|center|thumb|400px|'''Fig. 3 Predicted amino acid sequence of OsCHLH. The sequence was multiple-aligned with Arabidopsis '''''CHLH''''' (Z68495), soybean '''''CHLH''''' (AJ001091), tobacco '''''CHLH''''' (AF014052), and barley '''''XANTHAF''''' (U26916).''' '' <ref name="ref1" />.'']]
 ==Labs working on this gene==

← Older revision		Revision as of 11:11, 1 August 2016
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	* Transcript levels of the '''''OsCHLH''''' gene are increased by light. The researchers also found this induction by assaying the fusion product between '''''OsCHLH''''' and GUS.		* Transcript levels of the '''''OsCHLH''''' gene are increased by light. The researchers also found this induction by assaying the fusion product between '''''OsCHLH''''' and GUS.
		+
		+	* The '''''OsCHLH''''' gene is essential for rice plants. Knockout mutations of this gene result in a seedling-lethal phenotype. DNA gel-blot analysis of rice genomic DNA indicates only a single copy of the gene.
		+
		+	* The researchers suggest that the C-terminal region is essential for CHLH enzyme activity. Based on the RGP mapping data, '''''OsCHLH''''' is positioned near the chl2 locus on Chromosome 3.

	===Mutation===		===Mutation===

@@ Line 4: / Line 4: @@
 ===Function===
 * The '''''OsCHLH''''' gene encodes the largest subunit of the rice Mg-chelatase, a key enzyme in the chlorophyll branch of the tetrapyrrole biosynthetic pathway.
 ===Mutation===

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 </ref>
 * <ref name="ref2">
+Yamazaki, J., Kamimura, Y., Okada, M. and Sugimura, Y. (1999) Changes in photosynthetic characteristics and photosystem stoichiometries in the lower leaves in rice seedlings. Plant Sci. 148: 155–163.
 </ref>
 * <ref name="ref3">