Calcium function and distribution during fertilization in angiosperms

Ge, Li; Tian, Hui Qiao; Russell, Scott D.

doi:10.3732/ajb.94.6.1046

Cited by 111 publications

(99 citation statements)

References 188 publications

(152 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This possibly may explain the reverse phenotype observed in the calcium-supplemented GM. In vitro pollen germination of many species requires Ca 2+ (Brewbaker and Kwack, 1963;Ge et al, 2007), and Ca 2+ plays a central role during pollen germination (Brewbaker and Kwack, 1963;Ge et al, 2007;Hepler et al, 2012), acting putatively as a signal to activate the germination process and/or acting directly on the physical property of the intine. Ca 2+ dynamics have been investigated in Arabidopsis pollen grains during germination (Iwano et al, 2004).…”

Section: Discussionmentioning

confidence: 99%

PECTIN METHYLESTERASE48 Is Involved in Arabidopsis Pollen Grain Germination

et al. 2014

View full text Add to dashboard Cite

Germination of pollen grains is a crucial step in plant reproduction. However, the molecular mechanisms involved remain unclear. We investigated the role of PECTIN METHYLESTERASE48 (PME48), an enzyme implicated in the remodeling of pectins in Arabidopsis (Arabidopsis thaliana) pollen. A combination of functional genomics, gene expression, in vivo and in vitro pollen germination, immunolabeling, and biochemical analyses was used on wild-type and Atpme48 mutant plants. We showed that AtPME48 is specifically expressed in the male gametophyte and is the second most expressed PME in dry and imbibed pollen grains. Pollen grains from homozygous mutant lines displayed a significant delay in imbibition and germination in vitro and in vivo. Moreover, numerous pollen grains showed two tips emerging instead of one in the wild type. Immunolabeling and Fourier transform infrared analyses showed that the degree of methylesterification of the homogalacturonan was higher in pme482/2 pollen grains. In contrast, the PME activity was lower in pme482/2, partly due to a reduction of PME48 activity revealed by zymogram. Interestingly, the wild-type phenotype was restored in pme482/2 with the optimum germination medium supplemented with 2.5 mM calcium chloride, suggesting that in the wild-type pollen, the weakly methylesterified homogalacturonan is a source of Ca 2+ necessary for pollen germination. Although pollen-specific PMEs are traditionally associated with pollen tube elongation, this study provides strong evidence that PME48 impacts the mechanical properties of the intine wall during maturation of the pollen grain, which, in turn, influences pollen grain germination.

show abstract

Section: Discussionmentioning

confidence: 99%

PECTIN METHYLESTERASE48 Is Involved in Arabidopsis Pollen Grain Germination

et al. 2014

View full text Add to dashboard Cite

show abstract

“…plays an essential role during sexual plant reproduction (reviewed by Ge et al 2007): it is generally necessary for pollen germination, it determines the directionality of tube elongation and is required for the fusion of gametes. A tipfocused gradient of cytosolic-free calcium is present in growing pollen tubes and CAM activity has been reported to display a similar tip-focused gradient (Rato et al 2004).…”

Section: Discussionmentioning

confidence: 99%

A loss-of-function mutation in Calmodulin2 gene affects pollen germination in Arabidopsis thaliana

et al. 2010

View full text Add to dashboard Cite

Calmodulin (CAM) is an ubiquitous calcium binding protein whose function is to translate the signals, perceived as calcium concentration variations, into the appropriate cellular responses. In Arabidopsis thaliana there are 4 CAM isoforms which are highly similar, encoded by 7 genes, and one possible explanation proposed for the evolutionary conservation of the CAM gene family is that the different genes have acquired different functions so that they play possibly overlapping but non-identical roles. Here we report the characterization of the Arabidopsis mutant cam2-2, identified among the lines of the gene-trapping collection EXOTIC because of a distorted segregation of kanamycin resistance. Phenotypic analysis showed that in normal growth conditions cam2-2 plants were indistinguishable from the wild type while genetic analysis showed a reduced transmission of the cam2-2 allele through the male gametophyte and in vitro pollen germination revealed a reduced level of germination in comparison with the wild type. These results provide genetic evidence of the involvement of a CAM gene in pollen germination and support the theory of functional diversification of the CAM gene family.

show abstract

“…Além dos efeitos sobre o crescimento do tubo polínico (Krichevsky et al, 2007), os efeitos do cálcio na fertilização de flores incluem a atração, a comunicação a curtas distâncias, a fusão celular e a sinalização, de modo que o primeiro evento celular, observado após a fusão de gametas, é o aumento da concentração citossólica de cálcio, seguido pelo aumento da taxa de divisão celular (Ge et al, 2007), o que evidencia sua importância no desenvolvimento reprodutivo de plantas.…”

Section: Introductionunclassified

Fisiologia e produção da soja tratada com cinetina e cálcio sob deficit hídrico e sombreamento

Fioreze

Rodrigues²,

Carneiro

et al. 2013

Pesq. agropec. bras.

View full text Add to dashboard Cite

Resumo -O objetivo deste trabalho foi avaliar o efeito da cinetina e do cálcio sobre as características fisiológicas e produtivas de plantas de soja submetidas a estresses por deficit hídrico e sombreamento na fase de florescimento. Utilizou-se o delineamento de blocos ao acaso, em arranjo de parcelas subdivididas com quatro repetições. Plantas de soja cultivadas em vasos de 38 dm 3 foram submetidas à aplicação de cálcio e cinetina, de forma isolada e combinada, no início do florescimento e, em seguida, submetidas a estresse por deficit hídrico e por sombreamento por 12 dias. Após o período de estresse, as plantas foram conduzidas até a maturação com suprimento adequado de água e radiação. A aplicação de cálcio e cinetina promoveu a manutenção do conteúdo relativo de água nas plantas, após quatro dias de deficit hídrico. O extravasamento de eletrólitos celulares, medido ao final do período de estresse, foi menor em plantas tratadas com cálcio e cinetina. A assimilação de CO 2 foi reduzida pela imposição do estresse, principalmente do deficit hídrico, e a produção de grãos nos dois ambientes foi reduzida na mesma intensidade. Termos de indexação:Glycine max, ácido abscísico, assimilação de CO 2 , florescimento, hormônios vegetais. Physiology and yield of soybean treated with kinetin and calcium under drought and shade conditionsAbstract -The objective of this work was to evaluate the effects of kinetin and calcium applications on the physiologic and productive traits of soybean plants, subjected to drought and shade conditions, at flowering. A randomized complete block design was used, in a split-plot arrangement, with four replicates. Soybean plants cultivated in 38 dm 3 pots were sprayed with calcium and kinetin, alone or mixed, and subjected to drought and shade during 12 days. After stress period, plants were cultivated under appropriate water and light availability. Calcium and kinetin application resulted in maintenance of the relative water content after four days of drought beginning. Membrane damage, measured at the end of stress period, was lower in plants sprayed with calcium and kinetin. CO 2 assimilation diminished by stress condition, mainly under drought, and grain yield decreased at the same intensity in both environments.

show abstract

Calcium function and distribution during fertilization in angiosperms

Cited by 111 publications

References 188 publications

PECTIN METHYLESTERASE48 Is Involved in Arabidopsis Pollen Grain Germination

PECTIN METHYLESTERASE48 Is Involved in Arabidopsis Pollen Grain Germination

A loss-of-function mutation in Calmodulin2 gene affects pollen germination in Arabidopsis thaliana

Fisiologia e produção da soja tratada com cinetina e cálcio sob deficit hídrico e sombreamento

Contact Info

Product

Resources

About