The Role of Polar Movement of IAA in the Development of the Peg in Cucumis sativus L.

Witztum, A.; Gersani, Mordechai

doi:10.1086/336776

Cited by 35 publications

(50 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thereafter, a protuberance called a peg forms on the concave side of the bending transition zone (Witztum and Gersani, 1975; reviewed by Takahashi, 1997). The peg holds the seed coat during hypocotyl elongation and helps the cotyledons and the plumule to pull themselves out from the seed coat and to emerge from the soil.…”

Section: Introductionmentioning

confidence: 99%

Possible Involvement of CS-ACS1 and Ethylene in Auxin-induced Peg Formation of Cucumber Seedlings

et al. 2004

View full text Add to dashboard Cite

Background and Aims Cucumber (Cucumis sativus) seedlings develop a peg on the concave side of the gravitropically bending transition zone between the hypocotyl and the root after seed germination. Peg initiation occurs in response to auxin when its levels in the concave side of the transition zone exceed a particular threshold through the graviresponse. Ethylene also plays an important role in peg formation, but its relationship to auxin in this event is not understood. Here, the role ethylene plays in auxin-induced peg formation is studied.Methods Peg formation of cucumber seedlings exposed to ethylene at different stages of growth or during exogenous auxin treatment was observed. In addition, ethylene evolution from the concave and convex sides of the transition zone was compared and their transcription of CS-ACS (1-aminocyclopropane-1-carboxylic acid synthase) genes was analysed by RT-PCR and in situ hybridization.Key Results Seedlings treated with ethylene after peg initiation produced an enlarged peg, whereas ethylene treatment before peg initiation inhibited peg formation. Ethylene also promoted the development of the peg in the auxin-treated seedlings. Furthermore, the concave side of the transition zone at peg initiation produced more ethylene and CS-ACS1 mRNA than the convex side.Conclusions Since CS-ACS1 is an auxin-inducible gene, the greater abundance of auxin in the concave side of the transition zone causes peg initiation and increases CS-ACS1-mediated ethylene biosynthesis, which then facilitates peg development.

show abstract

Section: Introductionmentioning

confidence: 99%

Possible Involvement of CS-ACS1 and Ethylene in Auxin-induced Peg Formation of Cucumber Seedlings

et al. 2004

View full text Add to dashboard Cite

show abstract

“…Similar to other plant species, auxin transport in cucumber seedlings is thought to occur via polar transport from the cotyledons and/or apical meristems to the transition zone (Witztum and Gersani, 1975). In Arabidopsis, AtPIN1 localizes at the basal plasma membrane in xylem parenchyma cells and is responsible for the polar transport of auxin in stems (Gälweiler et al, 1998).…”

Section: Auxin Transport In the Transition Zone Of Cucumber Seedlingsmentioning

confidence: 99%

“…1). When cucumber (Cucumis sativus) seeds germinate in a horizontal position, a peg forms on the lower side of the transition zone (Witztum and Gersani, 1975; for review, see Takahashi, 1997;Fig. 1, A and B).…”

mentioning

confidence: 99%

“…Auxin plays an important role in gravimorphogenesis by determining the lateral placement of peg formation in the transition zone (Witztum and Gersani, 1975;Takahashi and Suge, 1988;Takahashi, 1997). Both endogenous indole-3-acetic acid (IAA) concentration and auxin-inducible gene expression are significantly reduced on the peg-suppressed side (the upper side) of the transition zone Kamada et al, 2000).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Gravistimulation Changes the Accumulation Pattern of the CsPIN1 Auxin Efflux Facilitator in the Endodermis of the Transition Zone in Cucumber Seedlings

Watanabe

Fujii²,

Yanai³

et al. 2011

Plant Physiology

View full text Add to dashboard Cite

Cucumber (Cucumis sativus) seedlings grown in a horizontal position develop a specialized protuberance (or peg) on the lower side of the transition zone between the hypocotyl and the root. This occurs by suppressing peg formation on the upper side via a decrease in auxin resulting from a gravitational response. However, the gravity-stimulated mechanism of inducing asymmetric auxin distribution in the transition zone is poorly understood. The gravity-sensing tissue responsible for regulating auxin distribution in the transition zone is thought to be the endodermal cell. To characterize the gravity-stimulated mechanism, the auxin efflux facilitator PIN-FORMED1 (CsPIN1) in the endodermis was identified and the localization of CsPIN1 proteins during the gravimorphogenesis of cucumber seedlings was examined. Immunohistochemical analysis revealed that the accumulation pattern of CsPIN1 protein in the endodermal cells of the transition zone of cucumber seedlings grown horizontally differed from that of plants grown vertically. Gravistimulation for 30 min prompted changes in the accumulation pattern of CsPIN1 protein in the endodermis as well as the asymmetric distribution of auxin in the transition zone. Furthermore, 2,3,5-triiodobenzoic acid inhibited the differential distribution of auxin as well as changes in the accumulation pattern of CsPIN1 in the endodermis of the transition zone during gravistimulation. These results suggest that the altered pattern of CsPIN1 accumulation in the endodermis in response to gravistimulation influences lateral auxin transport through the endodermis, resulting in asymmetric auxin distribution in the transition zone.

show abstract

“…and which serves to lever the integument off (Witztum and Gersani, 1975). After removal of the testa rapid hydrolysis of stored lipid commences (Slack et al, 1977).…”

Section: H V D a V I E S A N D P T S L A C Kmentioning

confidence: 99%

The Control of Food Mobilization in Seeds of Dicotyledonous Plants

Davies

Slack²

1981

New Phytologist

View full text Add to dashboard Cite

CONTENTS S U M M A R Y -Two alternative hypotheses can be used to explain how the embryo or embryonic axis controls food mobilization in seeds of many dicotyledonous plants. The first involves the production of a hormonal stimulus by the axis which initiates the development of optimal rates of hydrolytic enzyme activity in the storageorgans. The second involves the continualoperationof a source-sink relationship between the storage organs (source) and axis (sink) during germination and early seedling development. The evidence for the operation of these modes of control is discussed.

show abstract

The Role of Polar Movement of IAA in the Development of the Peg in Cucumis sativus L.

Cited by 35 publications

References 11 publications

Possible Involvement of CS-ACS1 and Ethylene in Auxin-induced Peg Formation of Cucumber Seedlings

Possible Involvement of CS-ACS1 and Ethylene in Auxin-induced Peg Formation of Cucumber Seedlings

Gravistimulation Changes the Accumulation Pattern of the CsPIN1 Auxin Efflux Facilitator in the Endodermis of the Transition Zone in Cucumber Seedlings

The Control of Food Mobilization in Seeds of Dicotyledonous Plants

Contact Info

Product

Resources

About