• 제목/요약/키워드: serpin

검색결과 30건 처리시간 0.025초

Mutations in the Reactive Center Loop of $\alpha_1$-Antitrypsin That Retard the Loop Insertion

  • Maeng, Jin-Soo;Yu, Myeong-Hee
    • 한국생물물리학회:학술대회논문집
    • /
    • 한국생물물리학회 1997년도 학술발표회
    • /
    • pp.40-40
    • /
    • 1997
  • $\alpha$$_1$- Antitrypsin is a key plasma serine protease inhibitor and its prime physiological role is an inhibitor of leukocyte elastase. The reactive center loop of $\alpha$$_1$-antitrypsin is characterized by the unusual mobility and the ability of insertion into the central $\beta$ sheet A. In particular the rate of loop insertion is considered to be critical for the formation of a stable complex between a serpin and its target protease.(omitted)

  • PDF

단백질의 구조 전환과 기능 조절 (Conformational Switch and Functional Regulation of Proteins)

  • 유명희
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
    • /
    • pp.3-6
    • /
    • 2001
  • In common globular proteins, the native form is in its most stable state. However, the native form of inhibitory serpins (serine protease inhibitors) and some viral membrane fusion proteins is in a metastable state. Metastability in these proteins is critical to their biological functions. Our previous studies revealed that unusual interactions, such as side-chain overpacking, buried polar groups, surface hydrophobic pockets, and internal cavities are the structural basis of the native metastability. To understand the mechanism by which these structural defects regulate protein functions, cavity-filling mutations of a 1-antitrypsin, a prototype serpin, were characterized. Increasing conformational stability is correlated with decreasing inhibitory activity. Moreover, the activity loss appears to correlate with the decrease in the rate of the conformational switch during complex formation with a target protease. We also increased the stability of a 1-antitrypsin greatly via combining various stabilizing single amino acid substitutions that were distributed throughout the molecule. The results showed that a substantial increase of stability, over 13 kcal/mol, affected the inhibitory activity with a correlation of 11% activity loss per kcal/mol. The results strongly suggest that the native metastability of proteins is indeed a structural design that regulates protein functions and that the native strain of a 1-antitrypsin distributed throughout the molecule regulates the inhibitory function in a concerted manner.

  • PDF

단백질의 구조 전환과 기능 조절 (Conformational Switch and Functional Regulation of Proteins)

  • 유명희
    • E2M - 전기 전자와 첨단 소재
    • /
    • 제14권12호
    • /
    • pp.3-6
    • /
    • 2001
  • In common globular proteins, the native form is n its most stable state. However, the native form of inhibitory serpins (serine protease inhibitors) and some viral membrane fusion proteins is in a metastable state. Metastability in these proteins is critical to their biological functions. Our previous studies revealed that unusual interactions, such as side-chain overpacking, buried polar groups, surface hydrophobic pockets, ad internal cavities are the structural basis of the native metastability. To understand the mechanism by which these structural defects regulate protein functions, cavity-filling mutations of $\alpha$1-antitrypsin, a prototype serpin, were characterized. Increasing conformational stability is correlated with decreasing inhibitory activity. Moreover, the activity loss appears to correlate with the decrease in the rate of the conformational switch during complex formation with a target protease. We also increased the stability of $\alpha$1-antitrypsin greatly via combining various stabilizing single amino acid substitutions that were distributed throughout the molecule. The results showed that a substantial increase of stability, over 13 kcal/mol, affected the inhibitory activity with a correlation of 11% activity loss per kcal/mol. The results strongly suggest that the native metastability of proteins is indeed a structural design that regulates protein functions and that the native strain of $\alpha$1-antitrypsin distributed throughout the molecule regulates the inhibitory function in a concerted manner.

  • PDF

Probing the movement of helix F region and the stepwise insertion of reactive site loop in $\alpha_1$-Antitrypsin variants

  • Baek, Je-Hyun;Lee, Cheolju;Kang, Un-Beom;Kim, Joon;Yu, Myeong-Hee
    • 한국생물물리학회:학술대회논문집
    • /
    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
    • /
    • pp.63-63
    • /
    • 2003
  • $\alpha$$_1$-Antityrpsin is a member of the serine protease inhibitor (SERPIN) family that shares a common tertiary structure. The reactive site loop (RSL) of serpins is exposed at one end of the molecule for protease binding. Upon cleavage by a target protease, the RSL is inserted into the major $\beta$-sheet A, which is a necessary process for formation of a tight inhibitory complex. Various biochemical and structural studies suggest that the rate of the RSL insertion upon binding a target protease is critical for inhibitory activity, and it is thought that helix F region (thFs3A and helix F) located in front of $\beta$-sheet A, should be lifted for the loop insertion during complex formation.

  • PDF

단백질의 구조 전환과 기능 조절 (Conformational Switch and Functional Regulation of Proteins)

  • 유명희
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
    • /
    • pp.3-6
    • /
    • 2001
  • In common globular proteins, the native form is in its most stable state. However, the native form of inhibitory serpins (serine protease inhibitors) and some viral membrane fusion proteins is in a metastable state. Metastability in these Proteins is critical to their biological functions. Our previous studies revealed that unusual interactions, such as side-chain overpacking, buried polar groups, surface hydrophobic pockets, and internal cavities are the structural basis of the native metastability. To understand the mechanism by which these structural defects regulate protein functions, cavity-filling mutations of ${\alpha}$1-antitrypsin, a prototype serpin, were characterized. Increasing conformational stability is correlated with decreasing inhibitory activity. Moreover, the activity loss appears to correlate with the decrease in the rate of the conformational switch during complex formation with a target protease. We also increased the stability of ${\alpha}$1-antitrypsin greatly via combining various stabilizing single amino acid substitutions that were distributed throughout the molecule. The results showed that a substantial increase of stability, over 13 kcal/mol, affected the inhibitory activity with a correlation of 11% activity loss per kcal/mol. The results strongly suggest that the native metastability of proteins is indeed a structural design that regulates protein functions and that the native strain of e 1-antitrypsin distributed throughout the molecule regulates the inhibitory function in a concerted manner.

  • PDF

Identification of Highly Transcribed Genes in Japanese Oak Silkworm, Antheraea yamamai, Using PCR-Based cDNA Library

  • Lee, Jin-Sung;Kim, Ki-Hwan;Goo, Tae-Won;Yun, Eun-Young;Kang, Seok-Woo;Suh, Dongs-Sang;Hwang, Jae-Sam
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제1권2호
    • /
    • pp.171-175
    • /
    • 2000
  • Determined sequences of 384 randomly selected clones in a PCR-based cDNA library of Antheraea yamamai could identify expressed sequence tags (ESTs) of highly expressed gene. One EST (fibroin) appeared 15 times, one EST (40S ribosomal protein S18) twelve times, one EST (ribosomal protein S24a) eleven times, ten times (ribosomal protein S8), nine times (60S ribosomal protein L10A), seven times (60S ribosomal protein S15A, S17, S17 and seroin), six times (ribosomal protein S8), five times (ribosomal protein S24, mariner transposase and P8 protein), four times (serpin 2), three times (heat shock protein 70 and poly A binding protein), and the remaining 6 ESTs twice (amylase, KIAA1006, elongation factor-1, transposon mag, translation initiation factor 4C, QM protein, transposase). Therefore, the 94 EST make it possible to identify 24 redundant clones that are candidates for highly expressed genes in posterior silk gland of this insect. The 24 redundant EST clones were identified in GenBank, but none of them was related to A. yamamai, suggesting that there are many unidentified genes which are highly expressed in the A. yamamai genome.

  • PDF

Association Analysis of SERPINB5 Polymorphisms with HBV Clearance and HCC Occurrence in a Korean Population

  • Kim, Ja-Son Y.;Park, Tae-Joon;Lee, Jin-Sol;Chun, Ji-Yong;Bae, Joon-Seol;Park, Byung-Lae;Cheong, Hyun-Sub;Lee, Hyo-Suk;Kim, Yoon-Jun;Shin, Hyoung-Doo
    • Genomics & Informatics
    • /
    • 제8권1호
    • /
    • pp.1-8
    • /
    • 2010
  • Serpin peptidase inhibitor, Clade B (ovalbumin), Member 5 (SERPINB5), also known as maspin, is a potent tumor suppressor gene. It has correlations with many tumor cells, from pancreas cancer to breast cancer, so it is possible that it may also affect liver cancer. There has also been a report that SERPINB12, a gene placed right next to SERPINB5, is expressed in liver. For this study, 32 polymorphisms were identified in SERPINB5 by direct DNA sequencing, and 11 of them were selected to be tested with a larger scale subjects. The association of the 11 SERPINB5 polymorphisms with Hepatitis B virus (HBV) clearance, hepatocellular carcinoma (HCC) occurrence and the onset age of HCC were analyzed. There were no significant associations found between 11 SERPINB5 polymorphisms and HBV clearance. In the case of HCC occurrence, one of the haplotypes (ht) showed association with HCC occurrence (OR=2.26, p=0.005, $P^{Cor}=0.05$), albeit with a low statistical power (40.8%) and haplotype frequency (0.052). Further study with a bigger sample size will be needed to clearly verify the association between ht5 and HCC occurrence.

비소세포폐암에서 Maspin의 발현과 임상적 의의 (Maspin Expression and Its Clinical Significance in Non-Small Cell Lung Cancer)

  • 윤성훈;김원진;신경화;김미현;조우현;김기욱;박혜경;전두수;김윤성;이창훈;이민기;박순규
    • Tuberculosis and Respiratory Diseases
    • /
    • 제70권2호
    • /
    • pp.132-138
    • /
    • 2011
  • Background: Maspin (mammary serine protease inhibitor) is a member of the serpin superfamily. A few studies have examined the role of maspin in tumor suppression of non-small cell lung cancer (NSCLC); however, its role in the development and progression of NSCLC still remains controversial. We evaluated the immunohistochemical expression of maspin in order to elucidate its clinical significance in NSCLC. Methods: We analyzed 145 patients with pathologically confirmed NSCLC, including 66 cases of squamous cell carcinomas (SCCs) and 79 cases of adenocarcinomas (ADCs). We performed a immuno-histochemical stain with maspin and PCNA (proliferating cell nuclear antigen) using tissue microarray blocks. Results: There were 108 men and 37 women in the study population. The mean age of patients in the study was 63.7 years (range, 40.0~82.0; median, 65.0). The proportion of maspin expression was significantly higher in SCCs (52/66, 78.8%; p<0.01) than in ADCs (17/79, 21.5%; p<0.01). Maspin expression was not associated with PCNA (p=0.828), lymph node involvement (p=0.483), or tumor stage (p=0.216), but showed correlation with well-to-moderate tumor differentiation (p=0.012). There was no observed correlation between maspin expression and survival with NSCLC (p=0.218). Conclusion: The present study suggests that maspin expression was significantly higher in SCCs than in ADCs and was associated with low histological grade. However, maspin expression was not an independent factor to predict a prognosis in NSCLC.

두경부 편평상피세포암 세포주의 염색체 이상 분석: 비교유전체보합법과 Array 비교유전체보합법 (Cytogenetic Analysis in Korean Head and Neck Cancer Cell Lines: Comparative Genomic Hybridization(CGH) and Array-CGH)

  • 신유리;박수연;이동욱;김한수;고영민;박현주;정성민
    • 대한두경부종양학회지
    • /
    • 제24권1호
    • /
    • pp.33-42
    • /
    • 2008
  • Head and neck squamous cell carcinoma(HNSCC) is notorious for its poor outcome and increasing incidence. But, the studies of cytogenetic analysis in HNSCC are relatively rare, because of difficulties in culturing solid tumor cells and complexity in chromosomal DNA abberations associated with the lesions. The purpose of this study is to evaluate the location of chromosomal aberrations in Korean HNSCC cell lines (SNU-1041, 1066, and 1076) with comparative genomic hybridization(CGH) and array based CGH(array-CGH). Chromosomal gains of 3q23-q27, 5p13-p15.3, 7p21-pter, 8q11.2-q12, 8q21.1-qter, 9q22-q34, 16q22-q24, and 20q11.2-qter, as well as chromosomal losses on 3p10-p14 were found in all 3 SNU cell lines. Losses on 3p15- p23, 4q22-q27, 4q31.3-qter, 6q14-q15, 7q31-q34, 8p12-pter, 18q21-q23, and 21q11.2-q12 were observed in 2 of 3 cell lines. In array-CGH, many genes were altered including gains of PIK3CA, MYC, EVI1, MAD1L1 genes and losses of SERPIN genes. These aberrations of gene and chromosome coincide with other results of study, generally. These data about the patterns of chromosomal aberrations could be a basic step for understanding more detailed genetic events in the carcinogenesis and also provide information for diagosis and treatment in HNSCC.

Identification of genes involved in inbreeding depression of reproduction in Langshan chickens

  • Xue, Qian;Li, Guohui;Cao, Yuxia;Yin, Jianmei;Zhu, Yunfen;Zhang, Huiyong;Zhou, Chenghao;Shen, Haiyu;Dou, Xinhong;Su, Yijun;Wang, Kehua;Zou, Jianmin;Han, Wei
    • Animal Bioscience
    • /
    • 제34권6호
    • /
    • pp.975-984
    • /
    • 2021
  • Objective: Inbreeding depression of reproduction is a major concern in the conservation of native chicken genetic resources. Here, based on the successful development of strongly inbred (Sinb) and weakly inbred (Winb) Langshan chickens, we aimed to evaluate inbreeding effects on reproductive traits and identify candidate genes involved in inbreeding depression of reproduction in Langshan chickens. Methods: A two-sample t-test was performed to estimate the differences in phenotypic values of reproductive traits between Sinb and Winb chicken groups. Three healthy chickens with reproductive trait values around the group mean values were selected from each of the groups. Differences in ovarian and hypothalamus transcriptomes between the two groups of chickens were analyzed by RNA sequencing (RNA-Seq). Results: The Sinb chicken group showed an obvious inbreeding depression in reproduction, especially for traits of age at the first egg and egg number at 300 days (p<0.01). Furthermore, 68 and 618 differentially expressed genes (DEGs) were obtained in the hypothalamus and ovary between the two chicken groups, respectively. In the hypothalamus, DEGs were mainly enriched in the pathways related to vitamin metabolism, signal transduction and development of the reproductive system, such as the riboflavin metabolism, Wnt signaling pathway, extracellular matrix-receptor interaction and focal adhesion pathways, including stimulated by retinoic acid 6, serpin family F member 1, secreted frizzled related protein 2, Wnt family member 6, and frizzled class receptor 4 genes. In the ovary, DEGs were significantly enriched in pathways associated with basic metabolism, including amino acid metabolism, oxidative phosphorylation, and glycosaminoglycan degradation. A series of key DEGs involved in folate biosynthesis (gamma-glutamyl hydrolase, guanosine triphosphate cyclohydrolase 1), oocyte meiosis and ovarian function (cytoplasmic polyadenylation element binding protein 1, structural maintenance of chromosomes 1B, and speedy/RINGO cell cycle regulator family member A), spermatogenesis and male fertility (prostaglandin D2 synthase 21 kDa), Mov10 RISC complex RNA helicase like 1, and deuterosome assembly protein 1) were identified, and these may play important roles in inbreeding depression in reproduction. Conclusion: The results improve our understanding of the regulatory mechanisms underlying inbreeding depression in chicken reproduction and provide a theoretical basis for the conservation of species resources.