• 한국버섯학회지
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• 제9권1호
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• pp.3-16
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• 2011

In the bipolar basidiomycete Pholiota nameko, a pair of homeodomain protein genes located at the A mating-type locus regulates mating compatibility. In the present study, we used a DNA-mediated transformation system in P. nameko to investigate the homeodomain proteins that control the clamp formation. When a single homeodomain protein gene (A3-hox1 or A3-hox2) from the A3 monokaryon strain was introduced into the A4 monokaryon strain, the transformants produced many pseudo-clamps but very few clamps. When two homeodomain protein genes (A3-hox1 and A3-hox2) were transformed either separately or together into the A4 monokaryon, the ratio of clamps to the clamp-like cells in the transformants was significantly increased to approximately 50%. We, therefore, concluded that the gene dosage of homeodomain protein genes is important for clamp formation. When the sip promoter was connected to the coding region of A3-hox1 and A3-hox2 and the fused fragments were introduced into NGW19-6 (A4), the transformants achieved more than 85% clamp formation and exhibited two nuclei per cell, similar to the dikaryon (NGW12-163 ${\times}$ NGW19-6). The results of real-time RT-PCR confirmed that sip promoter activity is greater than that of the native promoter of homeodomain protein genes in P. nameko. So, we concluded that nearly 100% clamp formation requires high expression levels of homeodomain protein genes and that altered expression of the A mating-type genes alone is sufficient to drive true clamp formation.

• BMB Reports
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• 제34권1호
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• pp.1-7
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• 2001

Structural and physical properties of type wild type and various selected mutants of the vnd/NK-2 homeodomain, the protein product of the homeobox, and the implication in genetic disease are reviewed. The structure, dynamics and thermodynamics have been Investigated by NMR and by calorimetry. The interactions responsible for the nucleotide sequence-specific binding of the homeodomain to its consensus DNA binding site have been identified. There is a strong correlation between significant structural alterations within the homeodomain or its DNA complex and the appearance of genetic disease. Mutations in positions known to be important in genetic disease have been examined carefully For example, mutation of position 52 of vnd/NK-2 results in a significant structural modification and mutation of position 54 alters the DNA binding specificity and amity The $^{15}N$ relaxation behavior and heteronuclear Overhauser effect data was used to characterize and describe the protein backbone dynamics. These studies were carried out on the wild type and the double mutant proteins both in the free and in the DNA bound states. Finally, the thermodynamic properties associated with DNA binding are described for the vnd/NK-2 homeodomain. These thermodynamic measurements reinforce the hypothesis that water structure around a protein and around DNA significantly contribute to the protein-DNA binding behavior. The results, taken together, demonstrate that structure and dynamic studies of proteins combined with thermodynamic measurements provide a significantly more complete picture of the solution behavior than the individual studies.

• BMB Reports
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• 제37권3호
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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.

• 생명과학회지
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• 제12권2호
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• pp.173-181
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• 2002

북미산 S. commune UVMl-34의 A $\alpha$ 3 mating locus를 지니는 cosmid clone pSC13의 mating activity에 필요한 sequence 함유여부를 확인한 후 sequencing을 행하고 이에 대한 비교분석을 실시하였다. 그 결과 blast program을 사용한 전체 nucleotide 염기서열의 homology비교분석에서 남미산 1-71에 패하여 약 96%의 높은 homology를 나타내었으며, 1-71 A $\alpha$ 3 mating locus에서 모두 7개로 추정되는 exon의 염기서열의 비교실험에서도 거의 96% 이상에 이르는 homology를 나타내었다. 부분적으로는 AR (acidic rich region)에서 약 97%, HD (homeodomain)에서는 약 99%, BR (basic rich region)에서 약 97%, 그리고 Ser (serine rich regon)에서 약 95%의 높은 homology를 나타내어 지역간에 유전자상의 큰 변화는 나타나지 않는 것으로 확인되었다. 그리고 translated polypeptide sequence 를 이용하여 자생지가 다른 남미산 S. commune A $\alpha$ 3 mating locus 내의 Y-region은 비롯하여 다른 $A\alpha$ alleles내의 Y-region과 비교 분석한 결과 남미산에 대해 전체적으로 약 97%의 높은 homology를 나타내고 있지만 그 외 $A\alpha$ mating alllele gene의 Y-region과는 41~49%의 낮은 homology로 mating activity에 관여하고 있는 것으로 나타났다. 특히 mating에 있어 transcription regulator로 알려진 homeodomain에서는 약 98%의 homology가 나타남으로서 Z-region의 74%에 비하여 대륙간에 상당히 높은 유전자 보존상이 확인되었다. 또한 AR에서 97%, BR에서 100% 그리고 Ser에서도 98%의 상당히 높은 homology를 지니는 사실을 확인하였다. 이러한 결과로 보아 남미와 북미에 자생하는 같은 mating allele type간에는 상당히 높은 비율의 염기서열 보존이 이루어지고 있음을 알 수 있었으며, 비록 다른 $A\alpha$ alleles간의 비교 이지만 다른 mating alleles간의 약 50% homology와 비교할 때 보다 상당히 높은 결과로 보인다. 특히 homeodomain motif의 비교에서 Y1을 비롯한 다른 mating allele gene과도 85% 이상의 높은 homology를 나타내었으며 그 외 AR, BR, Ser 부위에서는 10~50%에 이르는 낮은 비율로 나타났다.

• BMB Reports
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• 제43권6호
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• pp.407-412
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• 2010

Homeodomain (HD) is a highly conserved DNA-binding domain composed of helix-turn-helix motif. Drosophila Vnd (Ventral nervous system defective) containing HD acts as a regulator to either enhance or suppress gene expression upon binding to its target sequence. In this study, kinetic analysis of Vnd binding to DNA was performed. The result demonstrates that DNA-binding affinity of the recombinant protein containing HD and NK2-specific domain (NK2-SD) was higher than that of the full-length Vnd. To access whether phosphorylation sites within HD and NK2-SD affect the interaction of the protein with the target sequence, alanine substitutions were introduced. The result shows that S631A mutation within NK2-SD does not contribute significantly to the DNA-binding affinity. However, S571A and T600A mutations within HD showed lower affinity for DNA binding. In addition, DNA-binding analysis using embryonic nuclear protein also demonstrates that Vnd interacts with other nuclear proteins, suggesting the existence of Vnd as a complex.

• BMB Reports
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• 제47권2호
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• pp.92-97
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• 2014

We have examined the effect of bithorax complex genes on the expression of castor gene. During the embryonic stages 12-15, both Ultrabithorax and abdominal-A regulated the castor gene expression negatively, whereas Abdominal-B showed a positive correlation with the castor gene expression according to real-time PCR. To investigate whether ABD-B protein directly interacts with the castor gene, electrophoretic mobility shift assays were performed using the recombinant ABD-B homeodomain and oligonucleotides, which are located within the region 10 kb upstream of the castor gene. The results show that ABD-B protein directly binds to the castor gene specifically. ABD-B binds more strongly to oligonucleotides containing two 5'-TTAT-3' canonical core motifs than the probe containing the 5'-TTAC-3' motif. In addition, the sequences flanking the core motif are also involved in the protein-DNA interaction. The results demonstrate the importance of HD for direct binding to target sequences to regulate the expression level of the target genes.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.42-42
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• 2014

Mating of tetrapolar mushrooms is regulated by to chromosomal loci, A and B. A locus contains A gene that expresses a homeodomain protein whereas B locus contains multiple pheromones and receptor genes. In order to characterize the mating loci in Korean cultivated strains of Lentinula edodes, one hundred monokaryotic myclelia were isolated from the basidiospores of cultivated strains, including Cham-A-Ram, Sanjo701, and Sanjo707. Both mating loci were amplified using primer sets targeting conserved sequence regions for homeodomain (HD), pheromone, and receptor genes. Subsequent sequence analysis revealed that the Korean strains contained significant variations in the homeodomain of A locus, even within the same A1 or A2 mating type. Similarly, B locus was also highly diversified in the sequences of pheromones and receptors as well as gene organization. These results enabled us to design mating type-specific probes which can distinguish mating type of each strain. The specificity was confirmed by between intra- and inter-strain mating experiment.

• 생명과학회지
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• 제21권2호
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• pp.194-201
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• 2011

Caudal homeodomain 단백질은 초파리에서 사람에 이르기까지 보존되어 있으며, 장조직의 발생과 유지에 필수적인 역할을 한다. CDX1과 CDX2의 발현 감소 혹은 소실이 대장암과 연관되어 있음이 잘 알려져 있다. 대장암 발생은 산화성 스트레스와 밀접한 관련이 있으며, 대장암 조직에서 항산화효소인 catalase의 발현이 감소되어 있다. 하지만 그 분자적 기전은 잘 밝혀져 있지 않다. 본 연구에서는 초파리와 사람의 caudal homeodomain 단백질들이 catalase의 발현을 조절하는 것을 보여준다. 초파리 caudal heterozygous 돌연변이체의 대장조직에서 catalase의 발현이 감소되어 있고 ROS 생성이 증가되어 있음을 관찰하였다. 그리고 caudal 유전자의 과발현에 의해 catalase promoter의 활성과 mRNA 수준이 각각 증가함을 확인하였다. 또한 사람의 대장암 세포주인 HCT116 세포에서 CDX1과 CDX2가 catalase promoter의 활성과 단백질 수준에서 catalase를 상향 조절함을 관찰하였다. 이러한 결과들은 CDX1과 CDX2가 catalase 발현 조절을 통하여 장의 항상성 유지와 암발생 과정에 관여함을 시사한다.

• 한국동물학회:뉴스레터
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• 제12권2호
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• pp.121.1-121
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• 1995

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.334.1-334
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• 1995