Limits...
A cotton annexin protein AnxGb6 regulates fiber elongation through its interaction with actin 1.

Huang Y, Wang J, Zhang L, Zuo K - PLoS ONE (2013)

Bottom Line: Here we cloned six Annexin genes (AnxGb) abundantly expressed in fiber from sea-island cotton (G. barbadense). qRT-PCR results indicated that all six G. barbadense annexin genes were expressed in elongating cotton fibers, while only the expression of AnxGb6 was cotton fiber-specific.Analysis of AnxGb6 expression in three cotton genotypes with different fiber length confirmed that AnxGb6 expression was correlated to cotton fiber length, especially fiber elongation rate.Our results demonstrated that AnxGb6 was important for fiber elongation by potentially providing a domain for F-actin organization.

View Article: PubMed Central - PubMed

Affiliation: Plant Biotechnology Research Center, SJTU-Cornell Institute of Sustainable Agriculture and Biotechnology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.

ABSTRACT
Annexins are assumed to be involved in regulating cotton fiber elongation, but direct evidence remains to be presented. Here we cloned six Annexin genes (AnxGb) abundantly expressed in fiber from sea-island cotton (G. barbadense). qRT-PCR results indicated that all six G. barbadense annexin genes were expressed in elongating cotton fibers, while only the expression of AnxGb6 was cotton fiber-specific. Yeast two hybridization and BiFC analysis revealed that AnxGb6 homodimer interacted with a cotton fiber specific actin GbAct1. Ectopic-expressed AnxGb6 in Arabidopsis enhanced its root elongation without increasing the root cell number. Ectopic AnxGb6 expression resulted in more F-actin accumulation in the basal part of the root cell elongation zone. Analysis of AnxGb6 expression in three cotton genotypes with different fiber length confirmed that AnxGb6 expression was correlated to cotton fiber length, especially fiber elongation rate. Our results demonstrated that AnxGb6 was important for fiber elongation by potentially providing a domain for F-actin organization.

Show MeSH

Related in: MedlinePlus

Multiple sequence alignment analysis of AnxGb1-6 and other plant annexin proteins.Potential functional domains are indicated as follows: rectangle, Calcium binding site of type II G-X-GTD-{ca. 38}-E/D; black box, conserved tryptophan required for Ca2+-independent membrane binding; triangle, putative S3 cluster thought to be involved in redox reactions; grey, IRI motif for binding actin; circle, conserved His residue. Amino acid sequence alignment was performed using CLUSTALW. Accession numbers are as follows: AnxAt1 (NP174810); AnxAt 2 (NP201307); AnxZm33 (NP001105728); AnxZm35 (NP001105475); AnxGh1 (AAR13288).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3672135&req=5

pone-0066160-g001: Multiple sequence alignment analysis of AnxGb1-6 and other plant annexin proteins.Potential functional domains are indicated as follows: rectangle, Calcium binding site of type II G-X-GTD-{ca. 38}-E/D; black box, conserved tryptophan required for Ca2+-independent membrane binding; triangle, putative S3 cluster thought to be involved in redox reactions; grey, IRI motif for binding actin; circle, conserved His residue. Amino acid sequence alignment was performed using CLUSTALW. Accession numbers are as follows: AnxAt1 (NP174810); AnxAt 2 (NP201307); AnxZm33 (NP001105728); AnxZm35 (NP001105475); AnxGh1 (AAR13288).

Mentions: A total of 6 G. barbadense annexin genes were cloned, each of which encodes a protein that was evolutionarily conserved and similar to the structure of annexin proteins from other plants (GenBank NO.: KC316004 to KC316009). The G. barbadense annexins were found to contain the conserved Ca2+-binding sites (G-X-GTD-(ca. 38)-E/D) and four annexin repeats with 70 amino acids at their C-terminals (Figure 1). All of the six proteins contained a heme binding motif of 30 amino acids, which contained the conserved His residue for heme binding similar to that in peroxidase from Armoracia rusticana[55]. The cotton proteins also contained S3 clusters putatively involved in redox reactions [56]. Interestingly, a potential F-actin binding motif (IRI) was found in AnxGb5 and 6, while AnxGb3 and 4 contained IRV amino acid residues at the same site [57].


A cotton annexin protein AnxGb6 regulates fiber elongation through its interaction with actin 1.

Huang Y, Wang J, Zhang L, Zuo K - PLoS ONE (2013)

Multiple sequence alignment analysis of AnxGb1-6 and other plant annexin proteins.Potential functional domains are indicated as follows: rectangle, Calcium binding site of type II G-X-GTD-{ca. 38}-E/D; black box, conserved tryptophan required for Ca2+-independent membrane binding; triangle, putative S3 cluster thought to be involved in redox reactions; grey, IRI motif for binding actin; circle, conserved His residue. Amino acid sequence alignment was performed using CLUSTALW. Accession numbers are as follows: AnxAt1 (NP174810); AnxAt 2 (NP201307); AnxZm33 (NP001105728); AnxZm35 (NP001105475); AnxGh1 (AAR13288).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3672135&req=5

pone-0066160-g001: Multiple sequence alignment analysis of AnxGb1-6 and other plant annexin proteins.Potential functional domains are indicated as follows: rectangle, Calcium binding site of type II G-X-GTD-{ca. 38}-E/D; black box, conserved tryptophan required for Ca2+-independent membrane binding; triangle, putative S3 cluster thought to be involved in redox reactions; grey, IRI motif for binding actin; circle, conserved His residue. Amino acid sequence alignment was performed using CLUSTALW. Accession numbers are as follows: AnxAt1 (NP174810); AnxAt 2 (NP201307); AnxZm33 (NP001105728); AnxZm35 (NP001105475); AnxGh1 (AAR13288).
Mentions: A total of 6 G. barbadense annexin genes were cloned, each of which encodes a protein that was evolutionarily conserved and similar to the structure of annexin proteins from other plants (GenBank NO.: KC316004 to KC316009). The G. barbadense annexins were found to contain the conserved Ca2+-binding sites (G-X-GTD-(ca. 38)-E/D) and four annexin repeats with 70 amino acids at their C-terminals (Figure 1). All of the six proteins contained a heme binding motif of 30 amino acids, which contained the conserved His residue for heme binding similar to that in peroxidase from Armoracia rusticana[55]. The cotton proteins also contained S3 clusters putatively involved in redox reactions [56]. Interestingly, a potential F-actin binding motif (IRI) was found in AnxGb5 and 6, while AnxGb3 and 4 contained IRV amino acid residues at the same site [57].

Bottom Line: Here we cloned six Annexin genes (AnxGb) abundantly expressed in fiber from sea-island cotton (G. barbadense). qRT-PCR results indicated that all six G. barbadense annexin genes were expressed in elongating cotton fibers, while only the expression of AnxGb6 was cotton fiber-specific.Analysis of AnxGb6 expression in three cotton genotypes with different fiber length confirmed that AnxGb6 expression was correlated to cotton fiber length, especially fiber elongation rate.Our results demonstrated that AnxGb6 was important for fiber elongation by potentially providing a domain for F-actin organization.

View Article: PubMed Central - PubMed

Affiliation: Plant Biotechnology Research Center, SJTU-Cornell Institute of Sustainable Agriculture and Biotechnology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.

ABSTRACT
Annexins are assumed to be involved in regulating cotton fiber elongation, but direct evidence remains to be presented. Here we cloned six Annexin genes (AnxGb) abundantly expressed in fiber from sea-island cotton (G. barbadense). qRT-PCR results indicated that all six G. barbadense annexin genes were expressed in elongating cotton fibers, while only the expression of AnxGb6 was cotton fiber-specific. Yeast two hybridization and BiFC analysis revealed that AnxGb6 homodimer interacted with a cotton fiber specific actin GbAct1. Ectopic-expressed AnxGb6 in Arabidopsis enhanced its root elongation without increasing the root cell number. Ectopic AnxGb6 expression resulted in more F-actin accumulation in the basal part of the root cell elongation zone. Analysis of AnxGb6 expression in three cotton genotypes with different fiber length confirmed that AnxGb6 expression was correlated to cotton fiber length, especially fiber elongation rate. Our results demonstrated that AnxGb6 was important for fiber elongation by potentially providing a domain for F-actin organization.

Show MeSH
Related in: MedlinePlus