Dataset Information

Gene dosage effect of WEE1 on growth and morphogenesis from arabidopsis hypocotyl explants.

ABSTRACT:

Background and aims

How plant cell-cycle genes interface with development is unclear. Preliminary evidence from our laboratory suggested that over-expression of the cell cycle checkpoint gene, WEE1, repressed growth and development. Here the hypothesis is tested that the level of WEE1 has a dosage effect on growth and development in Arabidospis thaliana. To do this, a comparison was made of the development of gain- and loss-of-function WEE1 arabidopsis lines both in vivo and in vitro.

Methods

Hypocotyl explants from an over-expressing Arath;WEE1 line (WEE1(oe)), two T-DNA insertion lines (wee1-1 and wee1-4) and wild type (WT) were cultured on two-way combinations of kinetin and naphthyl acetic acid. Root growth and meristematic cell size were also examined.

Key results

Quantitative data indicated a repressive effect in WEE1(oe) and a significant increase in morphogenetic capacity in the two T-DNA insertion lines compared with WT. Compared with WT, WEE1(oe) seedlings exhibited a slower cell-doubling time in the root apical meristem and a shortened primary root, with fewer laterals, whereas there were no consistent differences in the insertion lines compared with WT. However, significantly fewer adventitious roots were recorded for WEE1(oe) and significantly more for the insertion mutant wee1-1. Compared with WT there was a significant increase in meristem cell size in WEE1(oe) for all three ground tissues but for wee1-1 only cortical cell size was reduced.

Conclusions

There is a gene dosage effect of WEE1 on morphogenesis from hypocotyls both in vitro and in vivo.

SUBMITTER: Spadafora N

PROVIDER: S-EPMC3503502 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Gene dosage effect of WEE1 on growth and morphogenesis from arabidopsis hypocotyl explants.

Spadafora Natasha N Perrotta Lara L Nieuwland Jeroen J Albani Diego D Bitonti M Beatrice MB Herbert Robert J RJ Doonan John H JH Marchbank Angela M AM Siciliano Ilario I Lentz Grønlund Anne A Francis Dennis D Rogers Hilary J HJ

Annals of botany 20121011 8

<h4>Background and aims</h4>How plant cell-cycle genes interface with development is unclear. Preliminary evidence from our laboratory suggested that over-expression of the cell cycle checkpoint gene, WEE1, repressed growth and development. Here the hypothesis is tested that the level of WEE1 has a dosage effect on growth and development in Arabidospis thaliana. To do this, a comparison was made of the development of gain- and loss-of-function WEE1 arabidopsis lines both in vivo and in vitro.<h4 ...[more]

PMID: 23065633

Similar Datasets

Project description:Plant stature and shape are largely determined by cell elongation, a process that is strongly controlled at the level of the cell wall. This is associated with the presence of many cell wall proteins implicated in the elongation process. Several proteins and enzyme families have been suggested to be involved in the controlled weakening of the cell wall, and these include xyloglucan endotransglucosylases/hydrolases (XTHs), yieldins, lipid transfer proteins and expansins. Although expansins have been the subject of much research, the role and involvement of expansin-like genes/proteins remain mostly unclear. This study investigates the expression and function of AtEXLA2 (At4g38400), a member of the expansin-like A (EXLA) family in arabidposis, and considers its possible role in cell wall metabolism and growth.Transgenic plants of Arabidopsis thaliana were grown, and lines over-expressing AtEXLA2 were identified. Plants were grown in the dark, on media containing growth hormones or precursors, or were gravistimulated. Hypocotyls were studied using transmission electron microscopy and extensiometry. Histochemical GUS (?-glucuronidase) stainings were performed.AtEXLA2 is one of the three EXLA members in arabidopsis. The protein lacks the typical domain responsible for expansin activity, but contains a presumed cellulose-interacting domain. Using promoter::GUS lines, the expression of AtEXLA2 was seen in germinating seedlings, hypocotyls, lateral root cap cells, columella cells and the central cylinder basally to the elongation zone of the root, and during different stages of lateral root development. Furthermore, promoter activity was detected in petioles, veins of leaves and filaments, and also in the peduncle of the flowers and in a zone just beneath the papillae. Over-expression of AtEXLA2 resulted in an increase of >10 % in the length of dark-grown hypocotyls and in slightly thicker walls in non-rapidly elongating etiolated hypocotyl cells. Biomechanical analysis by creep tests showed that AtEXLA2 over-expression may decrease the wall strength in arabidopsis hypocotyls.It is concluded that AtEXLA2 may function as a positive regulator of cell elongation in the dark-grown hypocotyl of arabidopsis by possible interference with cellulose metabolism, deposition or its organization.

Dataset Information

Gene dosage effect of WEE1 on growth and morphogenesis from arabidopsis hypocotyl explants.

Background and aims

Methods

Key results

Conclusions

Publications

Gene dosage effect of WEE1 on growth and morphogenesis from arabidopsis hypocotyl explants.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure