The Arabidopsis ERECTA gene encodes a putative receptor protein kinase with extracellular leucine-rich repeats.

Abstract

Arabidopsis Landsberg erecta is one of the most popular ecotypes and is used widely for both molecular and genetic studies. It harbors the erecta (er) mutation, which confers a compact inflorescence, blunt fruits, and short petioles. We have identified five er mutant alleles from ecotypes Columbia and Wassilewskija. Phenotypic characterization of the mutant alleles suggests a role for the ER gene in regulating the shape of organs orlginating f" the shoot apical meristem. We cloned the ER gene, and here, we report that it encades a putative receptor protein klnase. The deduced ER protein contains a cytoplasmic protein kinase catalytic domain, a transmembrane region, and an extracellular domain consisting of leucine-rich repeats, which are thought to interact with other macromolecules. Our results suggest that cell-cell communication mediated by a receptor kinase has an important role in plant morphogenesis.

SbRLK1, a receptor-like protein kinase of Sorghum bicolor (L.) Moench that is expressed in mesophyll cells

“…The function of SbRLK1 could be similar to the function of the LRRcontaining receptor-like protein kinase ERECTA from Arabidopsis. The ERECTA RLK has been shown to regulate the shape of organs originating from the shoot apical meristem (Torii et al 1996). Another possibility is that SbRLK1 integrates extracellular signals that in¯u-ence the metabolism of mesophyll cells directly.…”

Impact oferectamutation on leaf serration differs betweenArabidopsisaccessions

“…It is well known that L.er harbors a loss-of-function mutation in ER (the er-1 allele). 2 Thus, this observation brings up the possibility that small leaf teeth of L.er are caused by the er mutation. To test this, we observed the leaf shape in the L.er background that carries the functional ER transgene derived from Col (L.erCER).…”

“…1 The leaf shape of er mutant has been described as being "round" with a short petiole in comparison to that of wild type. [1][2][3] The word "round" points out the fact that the ratio of length to width of leaves is reduced in er compared to that of the wild-type leaves. The phrase "round leaves of er mutant" may also evoke an idea that the mutant leaves have smooth margins by contrast to serrated margins of the wild-type leaves.…”

“…5 In the study, in which Columbia (Col) accession was used as wild type, though all combinations of double mutants in ER-family genes show toothless leaves, er single mutant (the null mutant allele called er-105) does not show apparent reduction in tooth growth than wild type leaves. 5 Another commonly used accession Landsberg erecta (L.er) is known to display round leaves with short petioles 2 . In addition, L.er shows smaller leaf teeth than Col 6 ( Fig.…”

Molecular physiology of brassinosteroids revealed by the analysis of mutants

“…A set of additional 18 bri1 alleles has been identi®ed, one of which carried a mutation that resulted in a detectable restriction fragment length polymorphism located within the BRI1 gene and thus strongly supported its map-based cloning . The gene BRI1 encodes a putative leucine-rich repeat (LRR) receptor-like kinase (RLK) showing striking similarities to other plant LRR-RLK genes such as CLAVATA1, ERECTA, or Xa21 (Song et al 1995;Torii et al 1996;Clark et al 1997). The proposed function of these genes is the transmission of signals responsible for the regulation of developmental processes that probably involve cell-cell communication or plant pathogen recognition.…”