• BMB Reports
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• v.37 no.3
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• pp.320-334
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• 2004

StMBF1 (Solanum tuberosum multiprotein bridging factor 1) is a plant member of the MBF1 family of transcriptional co-activators. In an attempt to understand the role of StMBF1, we analyzed its interaction with plant transcription factors of the homeodomain-leucine zipper (Hd-Zip) family, a group of proteins with a typical leucine zipper motif adjacent to a homeodomain. StMBF1 is able to interact in vitro with the Hd-Zip protein Hahb-4 both in the presence and absence of DNA. Upon binding, StMBF1 increases the DNA binding affinity of Hahb-4, and of another plant homeodomain containing protein from the GL2/Hd-Zip IV family, HAHR-1. The biological role of interactions is discussed in this paper.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.162-168
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• 2011

High salinity is a common stress condition that adversely affects plant growth and crop production. In response to various environmental stresses, plants activate a number of defense genes that function to increase the tolerance. To isolate Arabidopsis genes that are involved in abiotic stress responses, we carried out genetic screening using various mutant lines. Among them, the blh8 ($\b{B}$EL1-$\b{L}$ike $\b{H}$omeodomain $\underline{8}$) mutant specifically shows chlorotic phenotypes to ionic (specifically, $Na^+$ and $K^+$) stresses, but no differences in root growth. In addition, BLH8 is related to plant development and abiotic stress as predicted by a Graphical Gaussian Model (GGM) network program. It implies that BLH8 functions as a putative transcription factor related to abiotic stress responses. Collectively, our results show that gene network analysis is a useful tool for isolating genes involved in stress adaptation in plants.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.21-26
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• 2005

Homeotic proteins have pivotal roles during the development of both plant and animals. Many homeotic proteins exert control over cell fate in cells where their genes are not expressed, i.e., in a non-cell autonomous manner. Cell-to-cell communication, which delivers critical information for position-dependent specification of cell fate, is an essential biological process in multicellular organisms. In plants, there are two pathways for intercellular communication that have been identified: the ligand/receptor-mediated apoplastic pathway and the plasmodesmata-mediated symplasmic pathway. Regulatory proteins and RNAs traffic symplasmically via plasmodesmata and play a critical role in intercellular communication. Thus, the non-cell autonomous function of homeotic proteins can be explained by the recent discovery of cell-to-cell trafficking of proteins or RNAs. This article specifically focuses on understanding the intercellular movement of homeodomain proteins, a family of homeotic proteins.

• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.121-126
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• 1999

Calli were induced from the petiole explants of Pimpinella brachycarpa on MS medium supplemented with 0.5 mg/L 2,4-D and 0.1 mg/L BA after four weeks of culture. Compact clusters of small and dense cells among these calli were selected and suspension-cultured as the source of embryogenic calli. When transferred to MS medium with 0.1 mg/L NAA, the suspension-cultured cells grew to embryogenic callus. Somatic embryos derived from these embryogenic calli developed into plantlets. The cDNA library was constructed in the embryogenic callus and in order to screen the cDNA library, these cDNAs were plated at a density 1.5 $\times$ 10^5 plaques per 15 cm petridish. Among 19 clones showing preferential hybridization with petiole HD-Zip gene, five clones were obtained after second screening. Four clones among them, were highly homologous to P. brachycarpa shoot-tip Phz4 gene, but one clone, Phc5 was about 1.5 kb which has an extra 163 bp to 5' upstream of Phz4. The Phc5 was 1,531 bp containing poly A tails of 18 bases. ATG start codon for Phc5, was located at position 284 with an open reading frame of 906 by which encodes a polypeptide of 302 amino acids. The Phc5 protein revealed that the polypeptides between 135 and 195 contain a homeodomain as the `leucine zipper' motif.

• Genomics & Informatics
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• v.20 no.2
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• pp.19.1-19.15
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• 2022

Alfalfa (Medicago sativa) is an important food and feed crop which rich in mineral sources. The WUSCHEL-related homeobox (WOX) gene family plays important roles in plant development and identification of putative gene families, their structure, and potential functions is a primary step for not only understanding the genetic mechanisms behind various biological process but also for genetic improvement. A variety of computational tools, including MAFFT, HMMER, hidden Markov models, Pfam, SMART, MEGA, ProtTest, BLASTn, and BRAD, among others, were used. We identified 34 MsWOX genes based on a systematic analysis of the alfalfa plant genome spread in eight chromosomes. This is an expansion of the gene family which we attribute to observed chromosomal duplications. Sequence alignment analysis revealed 61 conserved proteins containing a homeodomain. Phylogenetic study sung reveal five evolutionary clades with 15 motif distributions. Gene structure analysis reveals various exon, intron, and untranslated structures which are consistent in genes from similar clades. Functional analysis prediction of promoter regions reveals various transcription binding sites containing key growth, development, and stress-responsive transcription factor families such as MYB, ERF, AP2, and NAC which are spread across the genes. Most of the genes are predicted to be in the nucleus. Also, there are duplication events in some genes which explain the expansion of the family. The present research provides a clue on the potential roles of MsWOX family genes that will be useful for further understanding their functional roles in alfalfa plants.

• Molecules and Cells
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• v.37 no.10
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• pp.734-741
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• 2014

Histone modifications on major transcription factor target genes are one of the major regulatory mechanisms controlling adipogenesis. Plant homeodomain finger 2 (PHF2) is a Jumonji domain-containing protein and is known to demethylate the histone H3K9, a repressive gene marker. To better understand the function of PHF2 in adipocyte differentiation, we constructed stable PHF2 knock-down cells by using the mouse pre-adipocyte cell line 3T3-L1. When induced with adipogenic media, PHF2 knock-down cells showed reduced lipid accumulation compared to control cells. Differential expression using a cDNA microarray revealed significant reduction of metabolic pathway genes in the PHF2 knock-down cell line after differentiation. The reduced expression of major transcription factors and adipokines was confirmed with reverse transcription- quantitative polymerase chain reaction and Western blotting. We further performed co-immunoprecipitation analysis of PHF2 with four major adipogenic transcription factors, and we found that CCATT/enhancer binding protein (C/EBP)${\alpha}$ and C/EBP${\delta}$ physically interact with PHF2. In addition, PHF2 binding to target gene promoters was confirmed with a chromatin immunoprecipitation experiment. Finally, histone H3K9 methylation markers on the PHF2-binding sequences were increased in PHF2 knock-down cells after differentiation. Together, these results demonstrate that PHF2 histone demethylase controls adipogenic gene expression during differentiation.