Interaction Analysis between the Arabidopsis Transcription Repressor VAL1 and Transcription Coregulators SIN3-LIKEs (SNLs)

Abstract

VIVIPAROUS1/ABSCISIC ACID INSENSITIVE3-LIKE1 (VAL1) encodes a DNA-binding B3 domain protein and plays essential roles in seed maturation and flowering transition by repressing genes through epigenetic silencing in Arabidopsis. SWI-INDEPENDENT3 (SIN3)-LIKEs (SNLs), which encode scaffold proteins for the assembly of histone deacetylase complexes and have six SIN3 homologues (SNL1–SNL6) in Arabidopsis thaliana, directly repress gene expression to regulate seed maturation and flowering transition. However, it remains unclear whether VAL1 and SNLs work together in repressing the expression of related genes. In this study, yeast two-hybrid and firefly luciferase complementation imaging assays revealed that VAL1 interacts with SNLs, which can be attributed to its own zinc-finger CW (conserved Cys (C) and Trp (W) residues) domain and the PAH (Paired Amphipathic Helices) domains of SNLs. Furthermore, pull-down experiments confirmed that the CW domain of VAL1 interacts with both intact protein and the PAH domains of SNLs proteins, and the co-immunoprecipitation assays also confirmed the interaction between VAL1 and SNLs. In addition, quantitative real-time PCR (qRT-PCR) analysis showed that VAL1 and SNLs were expressed in seedlings, and transient expression assays showed that VAL1 and SNLs were localized in the nucleus. Considered together, these results reveal that VAL1 physically interacts with SNLs both in vitro and in vivo, and suggest that VAL1 and SNLs may work together to repress the expression of genes related to seed maturation and flowering transition in Arabidopsis.

Identification of the Genes Encoding B3 Domain-Containing Proteins Related to Vernalization of Beta vulgaris

“…PRC2 was recruited to the target loci by the VAL1/VAL2-RY regulatory complex which comprised VIVIPAROUS1/ABI3-LIKE1 (VAL1) and VAL2 proteins [ 55 ]. A DNA-binding B3 domain protein was encoded by AtVAL1 in Arabidopsis, which was very important for seed maturation and floral transition [ 63 ]. Overexpression of VaRAV1 in grape cells enhanced its cold tolerance via regulating the expression of target genes involved in cell wall composition [ 64 ].…”

Arabidopsis SEC13B Interacts with Suppressor of Frigida 4 to Repress Flowering

“…The SEC13A, SEC13B, and SUF4 CDS were obtained from the Col-0 cDNA using gene-specific primers (Table S1). The fragments were constructed into the pGEX4T-1 or pET28a expression vector [37]. To detect the SEC13A-SUF4 and SEC13B-SUF4 interactions in vitro using pull-down assays, roughly equal amounts of GST-SEC13A, GST-SEC13B, and His-SUF4 were incubated at 16 • C for 14 h. The protein pull-down assays were conducted in accordance with the manufacturer's instructions, utilizing glutathione ligand resin affinity purification from Sigma-Aldrich (Darmstadt, Germany) [38].…”