PEELING WALLS1 encodes a GT106 protein required for seed surface integrity
- 1University of Florida
Abstract
Rhamnogalacturonan I (RG-I) is a major pectin domain and an important wall component for cell-cell adhesion. Arabidopsis seed mucilage serves as a powerful model to identify and characterize pectin-related enzymes, since this gelatinous capsule is composed predominantly of RG-I. Although multiple glycosyltransferase (GT) families participate in pectin biosynthesis, only a limited number of their members have been functionally characterized in vivo or biochemically characterized in vitro. In this study, we characterized the biological functions of PEELING WALLS1 (PEEL1), a Golgi-localized GT106 protein that is related to known RG-I rhamnosyltransferases (RRTs). Knocking out PEEL1, but not its close paralog PEEL1-LIKE (PEEL1L), led to patchy mucilage release from seeds upon hydration. However, RG-I content was not compromised in mucilage extracted from peel1 or peel1 peel1L mutant seeds. Treatment of seeds with a cation chelator restored mucilage expansion but failed to rescue the underlying defect in epidermal cell adhesion. Histological experiments and transgene complementation demonstrated that optimal expression of PEEL1 is required for the adhesion of primary walls to the seed surface. Collectively, these findings identify PEEL1 as a previously unrecognized contributor to primary cell wall adhesion and suggest that different RRT-related proteins contribute to unique pectic structures or localizations in vivo, rather than total mucilage RG-I abundance.
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BibTeX
@misc{vargas2026peeling,
title = {{PEELING WALLS1 encodes a GT106 protein required for seed surface integrity}},
author = {A. D. Gomez Vargas and T. Jacobson and C. Voiniciuc},
howpublished = {bioRxiv},
year = {2026},
month = sep,
doi = {10.64898/2026.09.18.752628},
url = {https://www.biorxiv.org/content/10.64898/2026.09.18.752628v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - PEELING WALLS1 encodes a GT106 protein required for seed surface integrity
AU - A. D. Gomez Vargas
AU - T. Jacobson
AU - C. Voiniciuc
PY - 2026
DA - 2026/09/18
PB - bioRxiv
DO - 10.64898/2026.09.18.752628
UR - https://www.biorxiv.org/content/10.64898/2026.09.18.752628v1
AB - Rhamnogalacturonan I (RG-I) is a major pectin domain and an important wall component for cell-cell adhesion. Arabidopsis seed mucilage serves as a powerful model to identify and characterize pectin-related enzymes, since this gelatinous capsule is composed predominantly of RG-I. Although multiple glycosyltransferase (GT) families participate in pectin biosynthesis, only a limited number of their members have been functionally characterized in vivo or biochemically characterized in vitro. In this study, we characterized the biological functions of PEELING WALLS1 (PEEL1), a Golgi-localized GT106 protein that is related to known RG-I rhamnosyltransferases (RRTs). Knocking out PEEL1, but not its close paralog PEEL1-LIKE (PEEL1L), led to patchy mucilage release from seeds upon hydration. However, RG-I content was not compromised in mucilage extracted from peel1 or peel1 peel1L mutant seeds. Treatment of seeds with a cation chelator restored mucilage expansion but failed to rescue the underlying defect in epidermal cell adhesion. Histological experiments and transgene complementation demonstrated that optimal expression of PEEL1 is required for the adhesion of primary walls to the seed surface. Collectively, these findings identify PEEL1 as a previously unrecognized contributor to primary cell wall adhesion and suggest that different RRT-related proteins contribute to unique pectic structures or localizations in vivo, rather than total mucilage RG-I abundance.
ER -