Le4 Is an Epicotyl Preferential Homologue of the Soybean Seed-Specific Le1 Lectin and the Vegetative Le3 Lectin Genes

• Published in: Plant molecular biology reporter Vol. 33; no. 6; pp. 1779 - 1789
• Main Authors: Chragh, Muhammad, Zolotarov, Yevgen, Saeed, Hanaa, Strömvik, Martina V.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-12-2015; Springer Nature B.V
• Subjects: Arabidopsis thaliana; Bioinformatics; Biomedical and Life Sciences; Glycine max; Life Sciences; Metabolomics; Original Paper; Plant biology; Plant Breeding/Biotechnology; Plant Sciences; Proteomics; Seedlings; Soybeans; Structure prediction; Lectin; hAT transposon; Gene expression; Promoter analysis; Homologs
• ISSN: 0735-9640; 1572-9818
• DOI: 10.1007/s11105-015-0873-y

Legume lectins play important roles in signaling and defense. The best known legume lectinin soybean [
Glycine max
(L.) Merr.] is the seed-specific soybean agglutinin (
Le1
). Recently, we showed that the promoters of two
Le1
homologues,
Le2
and
Le3
, drive β-glucuronidase (GUS) gene expression in transgenic
Arabidopsis thaliana
. In the present study, five lectin copies (
Le1
–
Le5
) were identified in the soybean genome sequence. Transcript profiles were investigated for
Le1
–
Le4
in 2-week-old soybean seedlings using real-time qPCR and compared with public RNA-Seq-based transcript profiles.
Le3
transcripts are preferentially present in leaves, flowers, and vegetative tissues, while
Le4
transcripts are preferentially present in seedling nodes and epicotyls. Whereas
Le2
and
Le5
are likely non-expressed pseudogenes,
Le3
and
Le4
were further investigated for possible tertiary structure and for presence of
cis
-regulatory promoter motifs. Models of LE3 and LE4 tertiary structures show high similarity to the LE1 structure, although differences in the active sites allow for differences in substrates. Our results also show that several interesting
cis
-regulatory motifs are present. Furthermore, we show that three duplication events have led to the formation of these five lectin genes, one event of which corresponds with the most recent soybean genome duplication at 13 Mya.