• Clinical and Experimental Pediatrics
• /
• 제48권11호
• /
• pp.1252-1255
• /
• 2005

TBG 결핍증은 X 염색체 장완의 TBG 유전자의 돌연변이에 의해서 발생하며, 낮은 총 $T_4$와총$T_3$, 정상 유리 $T_4$와 유리 $T_3$, 정상 TSH 농도를 특징으로 한다. 혈청 티록신글로불린 농도에 따라 완전 TBG 결핍증과 부분 TBG 결핍증으로 나눌 수 있으며, 적절하게 진단하지 못하면 불필요한 검사나 치료의 요인이 될 수 있다. 저자들의 완전 TBG 결핍증으로 진단된 2명의 남아에 대하여 TBG 유전자 분석을 시행하였다. 대상아들은 신생아 선별검사에서 측정된 낮은 총 $T_4$ 농도 때문에 내원하였다. 진찰 소견은 정상이었으며, 갑상선 기능 검사 상 유리 $T_4$, TSH 농도는 정상이었다. 방사면역측정법에 의한 혈청 TBG는 측정되지 않았다. 중합효소연쇄반응을 이용하여 4개의 TBG 유전자 엑손을 증폭한 후 자동염기서열분석을 시행하였다. 두 대상아에서 모두 엑손 4의 352번째 codon의 첫 번째 단일 뉴클레오티드 C의 결손에 의한 frameshift 돌연변이로 374번째 codon에 termination codon이 나타난 것을 확인하였다. 대상아의 어머니들에게서는 돌연변이 대립유전자와 정상 대립유전자의 이형접합체를 확인하였다. 한국인 TBG 결핍증의 역학과 유전적 특성을 규명하기 위한 더 광범위한 연구가 필요할 것으로 생각된다.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
• /
• pp.81.2-82
• /
• 2003

Plants have evolved along with pathogens, and they have developed sophisticated defense systems against specific microorganisms to survive. G-protons are considered one of the upstream signaling components working as a key for the defense signal transduction pathway. For activation and inactivation of G-protein, GTP-biding proteins are involved. GTP -binding proteins are found in all organisms. Small GTP-binding proteins, having masses of 21 to 30kD, belong to a superfamily, often named the Ras supefamily because the founding members are encoded by human Ras genes initially discovered as cellular homologs of the viral ras oncogene. Members of this supefamily share several common structural features, including several guanine nucleotide binding domains and an effector binding domain. However, exhibiting a remarkable diversity in both structure and function. They are important molecular switches that cycle between the GDP-bound inactive form into the GTP-bound active form through GDP/GTP replacement. In addition, most GTP-binding proteins cycle between membrane-bound and cytosolic forms. such as the RAC family are cytosolic signal transduction proteins that often are involved in processing of extracellular stimuli. Plant RAC proteins are implicated in regulation of plant cell architecture secondary wall formation, meristem signaling, and defense against pathogens. But their molecular mechanisms and functions are not well known. We isolated a RacB homolog from rice to study its role of defense against pathogens. We introduced the constitutively active and the dominant negative forms of the GTP-hinging protein OsRacB into the wild type rice. The dominant negative foms are using two forms (full-sequence and specific RNA interference with RacB). Employing southern, and protein analysis, we examine to different things between the wild type and the transformed plant. And analyzing biolistic bombardment of onion epidermal cell with GFP-RacB fusion protein revealed association with the nucle.

• Journal of Microbiology
• /
• 제33권2호
• /
• pp.128-131
• /
• 1995

Using differential hybridization, we selected the prk gene fortuitously from Schizosaccharomyces pombe homologous to RACK1 of rat which encodes the receptor for activated protein kinase C. The cDNA sequence of prk was determined and its deduced amino acid sequence was 76% homologous to RACK1 and had the feature of trimeric G protein bata subunit. The specific amino acid sequences required for the protein kinase C binding were also present in Prk as in the case of RACK1 protein. From these similarities, we suggest that the Prk is protein kinase C binding protein of S. prombe. The involvement of Prk in signal transduction mediated by protein kinase C remained to be studied.

• BMB Reports
• /
• 제34권2호
• /
• pp.95-101
• /
• 2001

Tissue transglutaminase (TGII, $G{\alpha}h$) belongs to a family of enzymes which catalyze post-translational modification of proteins by forming isopeptides via $Ca^{2+}$-dependent reaction. Although TGII-mediated formation of isopeptides has been implicated to play a role in a variety of cellular processes, the physiological function of TGII remains unclear. In addition to this Tease activity, TGII is a guanosine triphosphatase (GTPase) which binds and hydrolyzes GTP It is now well recognized that the GTPase action of TGII regulates a receptor-mediated transmembrane signaling, functioning as a signal transducer of the receptor. This TGII function signifies that TGII is a new class of GTP-binding regulatory protein (G-protein) that differs from "Classical" heterotrimeric G-proteins. Regulation of enzyme is an important biological process for maintaining cell integrity. This review summarizes the recent development in regulation of TGII that may help for the better understanding of this unique enzyme. Since activation and inactivation of GTPase of TGII are similar to the heterotrimeric G-proteins, the regulation of heterotrimeric G-protein in the transmembrane signaling is also discussed.

• 한국자기공명학회논문지
• /
• 제5권1호
• /
• pp.29-36
• /
• 2001

The structures of two VBS (viral binding site) RNAs, SL1 and SL2, of Yeast Saccharomyces cerevisiae vims have been studied by 2D and 3D NMR experiments. VBSs play a crucial role in viral particle binding to the plus strand and packaging of the RNA. The secondary structures of the two VBS RNAs share a common feature of the stem-internal loop-stem-hairpin loop structure although the size of the internal loops of SL1 and SL2 differs. 2D experiments were sufficient for fill assignments of SL1. However, isotope labeling of the sample and multidimensional experiments were required for 28-nucleotide-long SL2 due to the spectral overlap. Several 3D HCCH experiments have accomplished full assignment of SL2 RNA.

• Biomolecules & Therapeutics
• /
• 제21권6호
• /
• pp.423-434
• /
• 2013

The adoption of oligonucleotide aptamer is well on the rise, serving an ever increasing demand for versatility in biomedical field. Through the SELEX (Systematic Evolution of Ligands by EXponential enrichment), aptamer that can bind to specific target with high affinity and specificity can be obtained. Aptamers are single-stranded nucleic acid molecules that can fold into complex three-dimensional structures, forming binding pockets and clefts for the specific recognition and tight binding of any given molecular target. Recently, aptamers have attracted much attention because they not only have all of the advantages of antibodies, but also have unique merits such as thermal stability, ease of synthesis, reversibility, and little immunogenicity. The advent of novel technologies is revolutionizing aptamer applications. Aptamers can be easily modified by various chemical reactions to introduce functional groups and/or nucleotide extensions. They can also be conjugated to therapeutic molecules such as drugs, drug containing carriers, toxins, or photosensitizers. Here, we discuss new SELEX strategies and stabilization methods as well as applications in drug delivery and molecular imaging.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권11호
• /
• pp.1628-1633
• /
• 2001

A goat ${\beta}$-casein gene was cloned and sequenced. Our previous study had determined the nucleotide sequences of the 5' flanking region and the structural gene including all 9 exons. In the present study, investigations were done on the regulatory sequences in the 5' flanking region of the goat ${\beta}$-casein gene by aligning and comparing it with the same gene from other mammals. The results showed that -200/-1 bp of the 5' flanking sequences contained six conserved clusters, in which the sites of gene expression regulated by the transcription factor and hormone might exist. It showed that fourteen glucocorticoid receptor elements, two cAMP responsive elements, two SV40 virus enhancer core sequences, two OCT-1 binding elements and one CTF/NF-1 binding element were dispersed in the 5' flanking region of goat ${\beta}$-casein gene. Our findings are perhaps valuable for the elucidation of the molecular mechanisms that control the expression of the goat ${\beta}$-casein gene.

• Journal of Life Science
• /
• 제11권2호
• /
• pp.120-125
• /
• 2001

The pyrR gene of the pyrimidine biosynthesis (pyr) operon of the thermophile Bacillus caldolyticus, encoding a uracil phosphoribosyltransferase (UPRTase), turned to rely as a pyr operon regulator. It has been proposed that PyrR mediates transcriptional termination-antitermination at three intercistronic regions of the par operon (S.-Y Ghim and J. Neuhard, J. Bacteriol.,176, 3698-3707, 1994). In this research, a plasmid carrying the pyrR region of B. caldolyticus could restore a pyrimidine regulation in a pyrR mutant of B. subtilis. Expression of pyrR was found to increase 6-7 fold during pyrimidine starvation. Additionally, a highly conserved nucleotide sequence which may constitute the binding site for a PyrR protein (PyrR-binding loop) in transcript was staggested. Alternative antiterminator and terminator structures involving three conserved motifs in front of the pyrR, pyrP and pyrB genes, respectively, are proposed to account for the observed regulation pattern.

• 통합자연과학논문집
• /
• 제5권3호
• /
• pp.190-194
• /
• 2012

Human P-gp is one of the protein responsible for the multidrug resistance (MDR) develpment. MDR is a major cause of the cancer chemotherapy. In this paper, we performed homology modeling, docking study of papayriferic acid into the P-gp nucleotide binding domain (NBD2). For human P-gp, X-ray crystal structure is not known yet. We developed homology model for human NBD2 using HlyB ABC transporter structure (PDB code: 1XEF, resolution 2.5 ${\AA}$). Docking study was performed using Autodock. Docking result was analyzed, which shows that ligand docks into steroid binding site and interacts through hydrophobic and hydrophilic interactions.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2005년도 생물공학의 동향(XVI)
• /
• pp.473-473
• /
• 2005