Analysis of the spatial expression pattern of seven Kip related proteins (KRPs) in the shoot apex of Arabidopsis thaliana.
OBJECTIVE
Kip-related-proteins (KRPs), negative regulators of cell division, have recently been discovered in plants but their in planta function is as yet unclear. In this study the spatial expression of all seven KRP genes in shoot apices of Arabidopsis thaliana were compared.


METHODS
In situ hybridization analyses were performed on longitudinal sections of shoot apices from 2-month-old Arabidopsis plants.


RESULTS
The study provides evidence for different expression pattern groups. KRP1 and KRP2 expression is restricted to the endoreduplicating tissues. In contrast, KRP4 and KRP5 expression is mainly restricted to mitotically dividing cells. KRP3, KRP6 and KRP7 can be found in both mitotically dividing and endoreduplicating cells.


CONCLUSIONS
The results suggest differential roles for the distinct KRPs. KRP1 and KRP2 might specifically be involved in the establishment of polyploidy. In contrast, KRP4 and KRP5 might be involved in regulating the progression through the mitotic cell cycle. KRP3, KRP6 and KRP7 might have a function in both types of cell cycle.
Ormenese
Sandra
S
Laboratoire de Physiologie Végétale, Université de Liège, B22 Sart-Tilman, B-4000 Liège, Belgium. sandra.ormenese@ulg.ac.be
de Almeida Engler
Janice
J
De Groodt
Ruth
R
De Veylder
Lieven
L
Inzé
Dirk
D
Jacqmard
Annie
A
D017360:Arabidopsis / Q000033:anatomy & histology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017403:In Situ Hybridization; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; C483304:kinky pollen protein, Arabidopsis