Identification of Elements Responsible for Maternally-Silenced Imprinted Gene Expression of Upward Curly Leaf1, an F-box Protein Gene that Regulates Curly Leaf in Arabidopsis

• Published in: Journal of plant biology = Singmul Hakhoe chi Vol. 63; no. 5; pp. 337 - 346
• Main Authors: Hong, Jooyeon, Lee, Jaehoon, Jeong, Cheol Woong, Brooks, Janie Sue, Choi, Yeonhee, Lee, Jong Seob
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-10-2020; Springer Nature B.V; 한국식물학회
• Subjects: Alleles; Biomedical and Life Sciences; Deoxyribonucleic acid; DNA; DNA methylation; Endosperm; Epigenetics; F-box protein; Gene expression; Genomic imprinting; Leaves; Life Sciences; Phase transitions; Plant Breeding/Biotechnology; Plant Ecology; Plant Genetics and Genomics; Plant Sciences; Plant Systematics/Taxonomy/Biogeography; Polycomb group proteins; Proteasome 26S; Proteasomes; Proteins; Reporter gene; Research Article; Seeds; Transgenic plants; Ubiquitin-protein ligase; 생물학; DNA methylation; Endosperm; Promoter elements; Imprinting; Polycomb group
• ISSN: 1226-9239; 1867-0725
• DOI: 10.1007/s12374-020-09256-4

Upward Curly Leaf 1 (UCL1) is an
Arabidopsis thaliana
E3 ligase that targets the Curly Leaf (CLF) SET-domain polycomb-group (PcG) protein for degradation via the ubiquitin-26S proteasome system.
UCL1
is a paternally-expressed imprinted gene in the endosperm. To precisely locate the promoter elements required for
UCL1
imprinting pattern, various gene constructs were created in which the imprinting control region (ICR), endosperm-specific expression (ENSE) element, and/or the linker sequence were altered. By fusing these constructs with a GUS reporter gene, GUS expression patterns were monitored after reciprocal crosses with wild-type Columbia-0 allowing the determination of parent-of-origin expression. Analysis of publicly-available data on the
UCL1
promoter region facilitated the search for allele-specific DNA and H3K27 methylation patterns. Overall, three promoter elements are required for maternal repression of
UCL1
; the ICR sequence located from − 2.5 to − 2.4 kb upstream of the translation start site, a differentially methylated region 2 (DMR2) that overlaps the short
ATLINE1-1
transposable element in the linker region, and a minimal 271 bp ENSE element. In addition, DNA methylation patterns in the DMR2 contribute to the repression of the maternal
UCL1
allele. Our findings would help to understand how parent-of-origin epigenetic patterns are created and maintained in the endosperm.