In superrosid species, root epidermal cells differentiate into root hair cells and nonhair cells. In some superrosids, the root hair cells and nonhair cells are distributed randomly (Type I pattern), and in others, they are arranged in a position‐dependent manner (Type III pattern). The model plant Arabidopsis ( In this study, we analyzed superrosid species We identified We propose that in superrosids, diverse Type III species inherited the patterning GRN from a common ancestor, whereas Type I species arose by mutations in multiple lineages.
Expansins comprise a superfamily of plant cell wall loosening proteins that can be divided into four individual families (EXPA, EXPB, EXLA and EXLB). Aside from inferred roles in a variety of plant growth and developmental traits, little is known regarding the function of specific expansin clades, for which there are at least 16 in flowering plants (angiosperms); however, there is evidence to suggest that some expansins have cell‐specific functions, in root hair and pollen tube development, for example. Recently, two duckweed genomes have been sequenced (
- NSF-PAR ID:
- 10458901
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 101
- Issue:
- 3
- ISSN:
- 0960-7412
- Page Range / eLocation ID:
- p. 666-680
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary Arabidopsis thaliana ) adopts the Type III pattern, and the gene regulatory network (GRN) that controls this pattern has been defined. However, it is unclear whether the Type III pattern in other species is controlled by a similar GRN as in Arabidopsis, and it is not known how the different patterns evolved.Rhodiola rosea ,Boehmeria nivea , andCucumis sativus for their root epidermal cell patterns. Combining phylogenetics, transcriptomics, and cross‐species complementation, we analyzed homologs of the Arabidopsis patterning genes from these species.R. rosea andB. nivea as Type III species andC. sativus as Type I species. We discovered substantial similarities in structure, expression, and function of Arabidopsis patterning gene homologs inR. rosea andB. nivea , and major changes inC. sativus . -
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