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DELLA activity is required for successful pollen development in the Columbia ecotype of Arabidopsis.

Plackett AR, Ferguson AC, Powers SJ, Wanchoo-Kohli A, Phillips AL, Wilson ZA, Hedden P, Thomas SG - New Phytol. (2013)

Bottom Line: Loss of DELLA activity in the monocot rice (Oryza sativa) causes complete male sterility, but not in the dicot model Arabidopsis (Arabidopsis thaliana) ecotype Landsberg erecta (Ler), in which DELLA function has been studied most extensively, leading to the assumption that DELLA activity is not essential for Arabidopsis pollen development.Col-0 rga gai mutants, in contrast with the equivalent Ler phenotype, were entirely male sterile, caused by post-meiotic defects in pollen development, which were rescued by the reintroduction of DELLA into either the tapetum or developing pollen.We conclude that DELLA activity is essential for Arabidopsis pollen development.

View Article: PubMed Central - PubMed

Affiliation: Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.

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Microscopic analysis of rga-28 gai-td1 (Arabidopsis thaliana Col-0) pollen development. (a–j) Sections through wild-type (a, c, e, g, i) and rga-28 gai-td1 (Col-0) (b, d, f, h, j) anthers, encompassing developmental stages 5–6 (a, b), 7 (c, d), 8–9 (e, f), 11 (g, h) and 13 (i, j), as defined by Sanders et al. (1999). E, endothecium; dM, degenerating microspore; dT, degenerating tapetum; M, microspore; P, pollen; PMC, pollen mother cell; T, tapetum; Td, tetrad. (k–u) 4′,6-Diamidino-2-phenylindole (DAPI) fluorescence imaging of pollen nuclei in wild-type (k, m, o, q, s, u) and rga-28 gai-td1 (Col-0) (l, n, p, r, t) during development, showing tetrad formation (k–n), free unicellular microspores (o, p), polarized microspores (q), bicellular pollen (s) and mature tricellular pollen (u). rga-28 gai-td1 (Col-0) microspores do not polarize (p), and subsequently degenerate (r, t).
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fig04: Microscopic analysis of rga-28 gai-td1 (Arabidopsis thaliana Col-0) pollen development. (a–j) Sections through wild-type (a, c, e, g, i) and rga-28 gai-td1 (Col-0) (b, d, f, h, j) anthers, encompassing developmental stages 5–6 (a, b), 7 (c, d), 8–9 (e, f), 11 (g, h) and 13 (i, j), as defined by Sanders et al. (1999). E, endothecium; dM, degenerating microspore; dT, degenerating tapetum; M, microspore; P, pollen; PMC, pollen mother cell; T, tapetum; Td, tetrad. (k–u) 4′,6-Diamidino-2-phenylindole (DAPI) fluorescence imaging of pollen nuclei in wild-type (k, m, o, q, s, u) and rga-28 gai-td1 (Col-0) (l, n, p, r, t) during development, showing tetrad formation (k–n), free unicellular microspores (o, p), polarized microspores (q), bicellular pollen (s) and mature tricellular pollen (u). rga-28 gai-td1 (Col-0) microspores do not polarize (p), and subsequently degenerate (r, t).

Mentions: Anther and pollen development in rga-28 gai-td1 (Col-0) were examined microscopically to identify the cause of pollen lethality. Pollen mother cells (PMCs) were visible in both wild-type and mutant anthers (Fig.4a,b). Successful tetrad formation and microspore release were observed in wild-type anthers (Fig.4c,m), whereas, by contrast, although some tetrads in rga-28 gai-td1 anthers apparently progressed successfully to the free microspore stage (Fig.4n), abnormal meiotic products were frequently observed (Figs4d, S6). Post-meiotic rga-28 gai-td1 pollen development was also abnormal: wild-type microspores progressed through pollen mitosis to maturity (Fig.4o,q,s,u), but microspore nuclear polarization before pollen mitosis was not observed in rga-28 gai-td1 (Fig.4p), and microspores subsequently degenerated (Fig.4r,t).


DELLA activity is required for successful pollen development in the Columbia ecotype of Arabidopsis.

Plackett AR, Ferguson AC, Powers SJ, Wanchoo-Kohli A, Phillips AL, Wilson ZA, Hedden P, Thomas SG - New Phytol. (2013)

Microscopic analysis of rga-28 gai-td1 (Arabidopsis thaliana Col-0) pollen development. (a–j) Sections through wild-type (a, c, e, g, i) and rga-28 gai-td1 (Col-0) (b, d, f, h, j) anthers, encompassing developmental stages 5–6 (a, b), 7 (c, d), 8–9 (e, f), 11 (g, h) and 13 (i, j), as defined by Sanders et al. (1999). E, endothecium; dM, degenerating microspore; dT, degenerating tapetum; M, microspore; P, pollen; PMC, pollen mother cell; T, tapetum; Td, tetrad. (k–u) 4′,6-Diamidino-2-phenylindole (DAPI) fluorescence imaging of pollen nuclei in wild-type (k, m, o, q, s, u) and rga-28 gai-td1 (Col-0) (l, n, p, r, t) during development, showing tetrad formation (k–n), free unicellular microspores (o, p), polarized microspores (q), bicellular pollen (s) and mature tricellular pollen (u). rga-28 gai-td1 (Col-0) microspores do not polarize (p), and subsequently degenerate (r, t).
© Copyright Policy - open-access
Related In: Results  -  Collection

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fig04: Microscopic analysis of rga-28 gai-td1 (Arabidopsis thaliana Col-0) pollen development. (a–j) Sections through wild-type (a, c, e, g, i) and rga-28 gai-td1 (Col-0) (b, d, f, h, j) anthers, encompassing developmental stages 5–6 (a, b), 7 (c, d), 8–9 (e, f), 11 (g, h) and 13 (i, j), as defined by Sanders et al. (1999). E, endothecium; dM, degenerating microspore; dT, degenerating tapetum; M, microspore; P, pollen; PMC, pollen mother cell; T, tapetum; Td, tetrad. (k–u) 4′,6-Diamidino-2-phenylindole (DAPI) fluorescence imaging of pollen nuclei in wild-type (k, m, o, q, s, u) and rga-28 gai-td1 (Col-0) (l, n, p, r, t) during development, showing tetrad formation (k–n), free unicellular microspores (o, p), polarized microspores (q), bicellular pollen (s) and mature tricellular pollen (u). rga-28 gai-td1 (Col-0) microspores do not polarize (p), and subsequently degenerate (r, t).
Mentions: Anther and pollen development in rga-28 gai-td1 (Col-0) were examined microscopically to identify the cause of pollen lethality. Pollen mother cells (PMCs) were visible in both wild-type and mutant anthers (Fig.4a,b). Successful tetrad formation and microspore release were observed in wild-type anthers (Fig.4c,m), whereas, by contrast, although some tetrads in rga-28 gai-td1 anthers apparently progressed successfully to the free microspore stage (Fig.4n), abnormal meiotic products were frequently observed (Figs4d, S6). Post-meiotic rga-28 gai-td1 pollen development was also abnormal: wild-type microspores progressed through pollen mitosis to maturity (Fig.4o,q,s,u), but microspore nuclear polarization before pollen mitosis was not observed in rga-28 gai-td1 (Fig.4p), and microspores subsequently degenerated (Fig.4r,t).

Bottom Line: Loss of DELLA activity in the monocot rice (Oryza sativa) causes complete male sterility, but not in the dicot model Arabidopsis (Arabidopsis thaliana) ecotype Landsberg erecta (Ler), in which DELLA function has been studied most extensively, leading to the assumption that DELLA activity is not essential for Arabidopsis pollen development.Col-0 rga gai mutants, in contrast with the equivalent Ler phenotype, were entirely male sterile, caused by post-meiotic defects in pollen development, which were rescued by the reintroduction of DELLA into either the tapetum or developing pollen.We conclude that DELLA activity is essential for Arabidopsis pollen development.

View Article: PubMed Central - PubMed

Affiliation: Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.

Show MeSH
Related in: MedlinePlus