• BMB Reports
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• 제43권11호
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• pp.720-725
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• 2010

The small ubiquitin-like modifier (SUMO) proteins have been implicated in the pathology of a number of diseases, including neurodegenerative diseases. The conjugation machinery for SUMOylation consists of a number of proteins which are redox sensitive. Here, under oxidative stress ($100{\mu}M$ hydrogen peroxide), antioxidant ($100{\mu}M$ ascorbate) or control conditions 169 proteins were identified by electospray ionisation fourier transform ion cyclotron resonance mass spectrometry. The majority of these proteins (70%) were found to contain SUMOylation consensus sequences. From the remaining proteins a small number (12%) were found to contain possible SUMO interacting motifs. The proteins identified included DNA and RNA binding proteins, structural proteins and proteasomal proteins. Several of the proteins identified under oxidative stress conditions had previously been identified as SUMOylated proteins, thus validating the method presented.

• 생명과학회지
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• 제21권9호
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• pp.1226-1233
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• 2011

키네신은 신경세포에서 미세소관 위를 따라 소포들을 운반하는 분자 motor 단백질로 4개의 단백질로 구성되어있다. 신경세포내에서 발현하는 KIF5C가 세포 내에서 어떤 특정소포를 이동시키는가는 신경세포성장에서 중요문제이다. 이에 본연구는 KIF5C와 결합하는 단백질을 동정하기 위하여 효모 two-hybrid 방법을 사용하여 KIF5C와 특이적으로 결합하는 $\underline{S}$am68-$\underline{l}$ike $\underline{m}$ammalian protein 2 (SLM-2)을 확인하였다. $\underline{S}$ignal $\underline{T}$ransducers and $\underline{A}$ctivators of $\underline{R}$NA (STAR) family의 한 종류이며 RNA processing에 관여하는 RNA 결합단백질인 SLM-2는 KIF5s의 C-말단과 결합하며, 또한 SLM-2의 C-말단은 KIF5s와 결합하는데 필수영역이였다. 이러한 단백질간의 결합은 Glutathione S-transferase (GST) pull-down assay를 통하여 SAM68, SLM-1, SLM-2은 특이적으로 Kinesin-I과 결합함을 확인하였으며, SAM68의 항체로 면역침강한 결과 KIF5s와 mRNA는 같이 침강하였다. 신경 세포의 말단에는 돌기형성에 필요한 단백질들의 주형인 mRNA가 다수 존재하며, 이러한 mRNA는 세포의 중앙에서 세포의 말단쪽으로 이동하여야 하는데, 이번 연구 결과는 Kinesin-I이 특이적으로 mRNA을 운반할 것으로 예상된다.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1996년도 제10회 식물생명공학심포지움 고등식물 발생생물학의 최근 진보
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• pp.40-47
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• 1996

The promoters of a variety of plant genes are characterized by the presence of TGACG motif-containing sequences. These genes often exhibit quite diverse expression characteristics and in many case the TGACG-motif has been demonstrated to be essential for expression. Here we report the isolation and characterization of a soybean cDNA that encodes a novel basic/leucine zipper (bZIP) protein, STF1, that specifically interacts with Hex (TGACGTGG) and CRE (TGACGTCA) sequences. This protein contains a bZIP motif at C-teminus and an acidic domain at N-terminus. DNA binding specificities, heterodimer formation, and expression characteristics of STF1 were compared with a soybean TGA1 protein, STGA1. The soybean STF1 interacts with TGACG-sequences containing an ACGT core, while STGA1 requires TGACG as a sufficient binding sequence. The flanking sequences to the TGACG motif affected DNA binding of STF1 siginificantly. The STF1 mRNA is found mainly in dark grown soybean seedling with higher expression in apical and elongating hypocotyl, while STGA1 mRNA is highly abundant in roots of light grown plants. Furthermore, we demonstrate that STF1 heterodimerzes with G-box binding factorss (GBFs) which was not observed with TGA1. The fact that STF1 possesses both distinct DNA binding speficities and heterodimerization properties suggest that STF1 belongs to a new family of plant bZIP proteins which recognize the Hex/CRE motif.

• The Plant Pathology Journal
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• 제23권4호
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• pp.281-286
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• 2007

Interactions between viral proteins and host proteins are essential for virus replication. Especially, translation of viral genes completely depends on the host machinery. In potyviruses, interactions of genome-linked viral protein (VPg) with host translation factors including eIF4E, eIF(iso)4E, and poly(A)-binding protein (PABP) has previously been characterized. In this study, we investigated interactions between Soybean mosaic virus (SMV) viral proteins and host translation factors by yeast two-hybrid system. SMV VPg interacted with eIF4E, eIF(iso)4E, and PABP in yeast two-hybrid system, while SMV helper component proteinase (HC-pro) interacted with neither of those proteins. The interaction between SMV NIb and PABP was also detected. These results are consistent with those reported previously in other potyviruses. Interestingly, we found reproducible and specific interactions between SMV coat protein (CP) and PABP. Deletion analysis showed that the region of CP comprising amino acids 116 to 206 and the region of PABP comprising amino acids 520 to 580 are involved in CP/PABP interactions. Soybean library screening with SMV NIb by yeast two-hybrid assay also identified several soybean proteins including chlorophyll a/b binding preprotein, photo-system I-N subunit, ribulose 1,5-biphosphate carboxylase, ST-LSI protein, translation initiation factor 1, TIR-NBS type R protein, RNA binding protein, ubiquitin, and LRR protein kinase. Altogether, these results suggest that potyviral replicase may comprise a multi-protein complex with PABP, CP, and other host factors.

• Bulletin of the Korean Chemical Society
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• 제28권6호
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• pp.1010-1014
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• 2007

M1 RNA is the catalytic component of RNase P, a tRNA-processing enzyme in Escherichia coli. M1 RNA is produced in the cell by transcription of the rnpB gene and subsequent processing at the 3' end. The 3' flanking region of rnpB contains repeated sets of overlapping sequences coding for small proteins. The issue of whether these proteins are expressed remains to be established. In this study, we showed the expression of a small protein encoded by the first repeat within the 3' flanking region of rnpB. Interestingly, protein expression was increased at lower temperatures. The termination efficiency of rnpB terminators was decreased at lower temperatures, suggesting that antitermination is responsible for enhanced protein expression. Moreover, the purified small protein contained M1 RNA, implying a role as a specific RNA-binding protein.

• Molecules and Cells
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• 제37권1호
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• pp.1-8
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• 2014

Mammalian-cell messenger RNAs (mRNAs) are generated in the nucleus from precursor RNAs (pre-mRNAs, which often contain one or more introns) that are complexed with an array of incompletely inventoried proteins. During their biogenesis, pre-mRNAs and their derivative mRNAs are subject to extensive cis-modifications. These modifications promote the binding of distinct polypeptides that mediate a diverse array of functions needed for mRNA metabolism, including nuclear export, inspection by the nonsense-mediated mRNA decay (NMD) quality-control machinery, and synthesis of the encoded protein product. Ribonucleoprotein complex (RNP) remodeling through the loss and gain of protein constituents before and after pre-mRNA splicing, during mRNA export, and within the cytoplasm facilitates NMD, ensuring integrity of the transcriptome. Here we review the mRNP rearrangements that culminate in detection and elimination of faulty transcripts by mammalian-cell NMD.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.24-24
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• 1996

SecA protein of E. coli is essential for the translocation of various precursor proteins across the plasma membrane. Along with it, SecA protein interacts with precursor proteins, SecY/E, SecB and is an ATPase which has multiple ATP binding sites. There is little known about the regulation mechanism of the protein translocation machinery. (omitted)

• The Korean Journal of Physiology and Pharmacology
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• 제17권2호
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• pp.157-162
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• 2013

Insulin-like growth factor binding proteins (IGFBPs) are important components of insulin growth factor (IGF) signaling pathways. One of the binding proteins, IGFBP-5, enhances the actions of IGF-1, which include the enhanced proliferation of smooth muscle cells. In the present study, we examined the expression and the biological effects of IGFBP-5 in vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). The levels of IGFBP-5 mRNA and protein were found to be higher in the VSMC from SHR than in those from WKY. Treatment with recombinant IGFBP-5-stimulated VSMC proliferation in WKY to the levels observed in SHR. In the VSMCs of WKY, incubation with angiotensin (Ang) II or IGF-1 dose dependently increased IGFBP-5 protein levels. Transfection with IGFBP-5 siRNA reduced VSMC proliferation in SHR to the levels exhibited in WKY. In addition, recombinant IGFBP-5 significantly up-regulated ERK1/2 phosphorylation in the VSMCs of WKY as much as those of SHR. Concurrent treatment with the MEK1/2 inhibitors, PD98059 or U0126 completely inhibited recombinant IGFBP-5-induced VSMC proliferation in WKY, while concurrent treatment with the phosphatidylinositol-3 kinase inhibitor, LY294002, had no effect. Furthermore, knockdown with IGFBP-5 siRNA inhibited ERK1/2 phosphorylation in VSMC of SHR. These results suggest that IGFBP-5 plays a role in the regulation of VSMC proliferation via ERK1/2 MAPK signaling in hypertensive rats.

• Childhood Kidney Diseases
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• 제3권2호
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• pp.109-116
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• 1999

목적 : Insuln-like growth factor(IGF)-I및 -II는 성장인자로 일군의 IGF-binding protein(IGFBP)에 의하여 그 작용이 조절된다. IGF-I은 백서 신장에서 발견되고 대사효과와 성장효과를 갖고 있다. 이번 연구는 백서에서 신장발육과 허혈성 신손상 후 재생과정 동안에 IGFBP의 발현이 변화하는지를 보고자 한다. 방법 : 태생 15주부터 성숙 할때까지 백서 신장에서 IGFBP 발현의 변화를 알아보기 위해 Northern blotting을 시행하였고, 급성신부전 백서의 신장에서 IGF-IGBP axis의 변화를 보기 위해 Northern blotting과 Immunohisto-chemistry를 이용하였다. 결과 : IGFBP-1과 -3는 태생기에는 거의 발현되지 않다가 출생 후 7일째부터 성숙이 끝날 때까지 점진적으로 증가하였다. 반면에 IGFBP-2와 -5는 태생기에 많이 발현되고, IGFBP-2는 출생 후 7일째까지 IGFBP-5는 30일째까지 높은 농도를 유지하다가 급격히 감소하였다. 한편 IGFBP-4는 태생기에 중등도로 발현되는데 출생 후 증가하기 시작하여 7일째 가장 많이 발현되다가 급격히 감소하였다. 신손상 후 IGFBP의 변화를 보면 IGFBP-1과 -4는 재생기간 동안 3-5배 증가되다가 정상으로 회복된 반면 IGFBP-3와 IGFBP Related Protein-1(IGFBPrP-1) 은 신손상 1일째에는 약간 감소하다가 그후 증가하여 정상보다 약간 높은 수준을 유지하였다. 결론 : 백서 신장에서 신장구조나 기능의 발달, 분화 및 재생에 대한 IGF의 작용을 조절할 수 있는 IGFBP 발현에 현저한 변화가 있었다.

• Journal of Microbiology and Biotechnology
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• 제26권12호
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• pp.2019-2029
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• 2016

Zinc finger proteins are among the most extensively applied metalloproteins in the field of biotechnology owing to their unique structural and functional aspects as transcriptional and translational regulators. The classical zinc fingers are the largest family of zinc proteins and they provide critical roles in physiological systems from prokaryotes to eukaryotes. Two cysteine and two histidine residues ($Cys_2His_2$) coordinate to the zinc ion for the structural functions to generate a ${\beta}{\beta}{\alpha}$ fold, and this secondary structure supports specific interactions with their binding partners, including DNA, RNA, lipids, proteins, and small molecules. In this account, the structural similarity and differences of well-known $Cys_2His_2$-type zinc fingers such as zinc interaction factor 268 (ZIF268), transcription factor IIIA (TFIIIA), GAGA, and Ros will be explained. These proteins perform their specific roles in species from archaea to eukaryotes and they show significant structural similarity; however, their aligned amino acids present low sequence homology. These zinc finger proteins have different numbers of domains for their structural roles to maintain biological progress through transcriptional regulations from exogenous stresses. The superimposed structures of these finger domains provide interesting details when these fingers are applied to specific gene binding and editing. The structural information in this study will aid in the selection of unique types of zinc finger applications in vivo and in vitro approaches, because biophysical backgrounds including complex structures and binding affinities aid in the protein design area.