Kinesin Superfamily KIF1Balpha Protein Binds to the PDZ Domain of MALS-3 / 대한해부학회지

The Kinesin superfamily proteins (KIFs) make up a large superfamily of molecular motors that transport cargo such as vesicles, protein complexes, and organelles. KIF1Balpha is a monomeric motor that conveys mitochondria and plays an important role in cellular function. Here, we used the yeast two-hybrid system to identify the proteins that interacts with KIF1Balpha and found a specific interaction with the mammalian LIN-7 (MALS)-3/vertebrate homology of LIN-7 (Veri) and synaptic scaffolding molecule (S-SCAM). MALS-3 protein bound to the tail region of KIF1Balpha but not to other kinesin family members in the yeast two-hybrid assay. The "T-X-V" motif at the C-terminal end of KIF1Balpha is essential for interaction with MALS-3. In addition, this protein showed specific interactions in the Glutathione S-transferase (GST) pull-down assay. An antibody to MALS-3 specifically coimmunoprecipitated KIF1Balpha associated with MALS-3 from mouse brain extracts. These results suggest that MALS-3, as KIF1Balpha receptor, is involved in the KIF1Balpha-mediated transport.

Kinesin Superfamily KIF1A Protein Binds to Synaptotagmin XI / 대한해부학회지

The kinesin proteins (KIFs) make up a large superfamily of molecular motors that transport cargo such as vesicles, protein complexes, and organelles. KIF1A is a monomeric motor that conveys synaptic vesicle precursors and plays an important role in neuronal function. Here, we used the yeast two-hybrid system to identify the neuronal protein (s) that interacts with the tail region of KIF1A and found a specific interaction with synaptotagmin XI. The amino acid residues between 830 and 1300 of KIF1A are required for the interaction with synaptotagmin XI. KIF1A also bound to the tail region of synaptotagmin IV but not to other synaptotagmin in the yeast two-hybrid assay. KIF1A interacted with GST-synaptotagim XI fusion proteins, but not with GST alone. An antibody to synaptotagmin XI specifically co-mmunoprecipitated KIF1A associated with synaptotagimin from mouse brain extracts. These results suggest that KIF1A motor protein transports of synaptotagmin XI-containing synaptic vesicle precursors along microtubule.

Kinesin Superfamily KIF5 Proteins Bind to betaIII Spectrin

The kinesin proteins (KIFs) make up a large superfamily of molecular motors that transport cargo such as vesicles, protein complexes, and organelles. KIF5 is a heterotetrameric motor that conveys vesicles and plays an important role in neuronal function. Here, we used the yeast two-hybrid system to identify the neuronal protein (s) that interacts with the tail region of KIF5 and found a specific interaction with betaIII spectrin. The amino acid residues between 1394 and 1774 of betaIII spectrin were required for the interaction with KIF5C. betaIII spectrin also bound to the tail region of neuronal KIF5A and ubiquitous KIF5B but not to other kinesin family members in the yeast two-hybrid assay. In addition, these proteins showed specific interactions, confirmed by GST pull-down assay and co-immunoprecipitation. betaIII spectrin interacted with GST-KIF5 fusion proteins, but not with GST alone. An antibody to betaIII spectrin specifically co-immunoprecipitated KIF5s associated with betaIII spectrin from mouse brain extracts. These results suggest that KIF5 motor proteins transport vesicles or organelles that are coated with betaIII spectrin.

Study on Hepatitis B Virus Pre-S/S Gene Mutations in Children with Chronic Hepatitis B Infection

PURPOSE: Hepatitis B virus(HBV) with various mutations has been reported. The aims of this study were to investigate the frequency and manifestation of HBV pre-S/S mutations in children with chronic hepatitis B infection. METHODS: Sera from 17 children with chronic hepatitis B infection were analyzed by direct sequencing of polymerase chain reaction amplification of HBV DNA. Results: Seventeen cases of adr type were analyzed. The deletions in HBV pre-S region were observed in 3(17.6%) of 17 cases. Of 3 deleted cases, 2 had an in-phase deletion in the pre-S1 region spanning 18 bp. Another case had a 18 bp and 3 bp deletions in the pre-S1 region. Many point mutations in HBV pre-S region were detected in all cases and these mutations were observed more frequently in the pre-S2 region than the pre-S1 region. Six point mutations in the pre-S1 region were observed. Eight point mutations in pre-S2 region were observed. Point mutations in the S region were detected in 14(82.4%) of 17 cases. Among these, mutations of the "a" determinant were detected in 4(23.5%) of 17 cases. Mutations at codon 130 and at codon 146 were noted in 2 cases. Combined mutations at codon 124, 126, 146 and at 130, 131, 136, 146 were noted in the other 2 cases. Mutations except "a" determinant region included at codon 3, 29, 73, 120, 184, 214, 226, 227. CONCLUSION: These observations suggest that deletion and point mutations in HBV pre-S1, pre- S2 regions and point mutations in HBV S region are frequent in the children with chronic hepatitis B infection.

Mutations in Hepatitis B Virus Precore and Core Promotor in Children with Chronic Hepatitis B Infection - Comparison Between Vertical and Non-vertical Transmission

PURPOSE: The aims of this study were to investigate the frequencies and role of hepatitis B virus(HBV) precore and core promotor mutations in children with chronic hepatitis B infection. METHODS: Sera from 46 children with chronic hepatitis B infection were analyzed by direct sequencing of polymerase chain reaction product of HBV DNA. In this study, the patients were divided into vertical and non-vertical groups according to the mode of HBV transmission. Statistical analysis was performed by using Fisher's exact test. RESULTS: Forty-six adr type of HBV DNA were analyzed. The mutations in HBV precore region were observed in 12(26.1Yo) of 46 cases. The GA mutation of nucletide(nt) 1896 was observed in 5 cases(10.9Yo). The frequency of mutations in HBV precore region of the non-vertical group (6/16; 37.5Fo) was higher than that of the vertical group(6/30; 20M), but there was no statistical significance. The mutation in HBV core promotor region was observed in 40(87.0%) of 46 cases. The A-->T mutation of nt 1762 or G-->A mutation of nt 1764 were observed in 24(52.2%) of 46 cases, and 23 cases revealed combined mutation at both positions 1762 and 1764. The frequency of mutations in HBV core promotor region of the vertical group(28/30; 93.3Yo) was higher than that of the non-vertical group(12/16; 75.0M), but there was no statistical significance. The frequencies of mutations in HBV precore and core promotor regions of the HBeAg negative patients was higher than that of HBeAg positive patients, but there was no statistical significance. Also there were no significant correlations between the frequencies of mutations in HBV precore and core promotor regions and AST, ALT level or the level of HBV DNA. CONCLUSION: These observations suggest that mutations in HBV precore and core promotor regions were frequently detected in children with chronic hepatitis B infection. There were no statistical significant differences in the frequencies of mutations in HBV precore and core promotor regions between vertical and non-vertical transmission groups. (J Korean Pediatr Soc 2000; 43:779-791)

Hepatitis B Virus Precore and Core Promotor Mutations in Children with Chronic Hepatitis B Infection

PURPOSE: The aims of this study were to investigate the frequencies and role of hepatitis B virus(HBV) precore and core promotor mutations in children with chronic hepatitis B infection. METHODS: Sera from 31 children with chronic HBV infection were analyzed by direct sequencing of polymerase chain reaction amplification of HBV DNA. RESULTS: Twenty-nine adr type were analyzed. The mutations in HBV precore region were observed in 8(27.6%) of 29 cases. The G->A mutation of nucleotide 1896(A1896; stop codon) were observed in 4 cases(13.8%). The mutations in HBV core promotor region were observed in 27 (93.1%) of 29 cases. The G(1764)->A mutation(A1764) was observed in 14 cases(48.3%), and among these 12 cases combined with a A to T change at nucleotide 1762(T1762). The mutations in HBV precore region were obsereved in 4(21%) of 19 cases of HBeAg positive group and 9(90%) of 10 cases of HBeAg negative group. A1896 mutation was observed in 2 cases in both HBeAg positive and negative group, respectively. The mutations in HBV core promotor region were observed in 18(94.7%) of 19 cases of HBeAg positive group and 9(90%) of 10 cases of HBeAg negative group. T1762 mutation were observed in 6(31.6%) of 19 cases of HBeAg positive group and 6(60%) of 10 cases of HBeAg negative group(P=0.14). A1764 mutation was obsereved in 7 (36.8%) of 19 cases of HBeAg positive group and 7(70%) of 10 cases of HBeAg negative group (P=0.089). A1896 mutation was observed in 2(18.2%) of 11 cases in increased AST/ALT group and 2(11.1%) of 18 cases in normal AST/ALT group. A1764 and T1762 mutations were higher (61.1%) in AST/ALT increased group than those(27.3%) in AST/ALT normal group, but there was no statistical significance(P=0.077). CONCLUSION: Mutations in the precore and core promotor regions can be frequently detected in children with chronic HBV infection. T1762 and A1764 mutations were observed more frequently in HBeAg negative group and in AST/ALT increased group but there was no statistical significance.

Interferon Treatment on HBeAg Positive Chronic Hepatitis B with HBV Precore Mutant in Liver Tissue / 대한내과학회지

BACKGROUND: This study investigates the prevalance of HBV precore mutant in chronic B hepatitis patients and whether HBV precore mutants affect hepatic inflammation and response to interferon alfa. METHODS: HBV DNA in liver tissue from 48 chronic hepatitis patients was amplified by polymerase chain reaction. The HBV precore mutants were detected by direct sequencing of amplified PCR products. Thirty-three HBeAg-positive patients (Group 1: wild- type, Group 2: mixed) were received 3-6 MU INF three times a week for 4-6 months. We did follow-ups for at least six months(mean : Group 1-11.3, Group 2- 13.7 months). A complete responder was defined as persistent(>6 months) normalization of transaminase and loss of HBeAg and/or seroconversion. RESULTS: The HBV precore mutants were found in 15 cases(31.2%) among 48 patients: 7 cases(21.2%) in 33 HBeAg-positive patients and 8 cases(53.3%) in 15 HBeAg-negative patients. The HBV precore mutants were more frequently found in HBeAg-negative patients(p= 0.043). Differences in severity of hepatic pathology were not observed in the wild-type versus mutant-type chronic hepatitis B patients(p =1.00). Initial response rate was not significantly different between two Groups(p= 0.228), but complete response rate had a lower tendency in Group 2 (p=0.073). CONCLUSION: There is a tendency for HBV precore mutants to be less responsive to INF therapy than wild type. Therefore the patients with chronic hepatitis B should be treated as early as possible in natural history of their liver disease before the emergence of HBV precore mutants.

A Study on HBV Precore Mutant in Liver Tissues of Chronic Hepatitis B Patiets / 대한간학회지

BACKGROUND/AIMS: In order to determine the relationship between the HBV precore mutant and the severity of liver disease in Korea, we performed liver biopsies in patients with HBV related chronic liver disease and compared the types of mutations and histologic findings in the same liver tissue simultaneously. METHODS: HBV DNA in liver tissues was amplified by polymerase chain reaction (PCR). The precore mutants were detected by PCR-SSCP(single strand conformation polymorphism), cloning the amplified PCR products and direct sequencing for them. RESULTS: 1. HBV DNA was detected in liver tissues of 28 cases among 30 patients with PCR. And with SSCP, the most cases were mixed type infections. 2. The HBV precore mutants were found in 12 cases among the total number of 28 cases(42.9%) and all mutations were G to A change at nucleotide 1896, creating a stop codon at codon 28. However, 10 cases among 12 mutants were associated with simultaneous another mutation at different positions or regions;9 cases at core gene region, 2 cases at nucleotide 1856(C to T change at codon 15), one case at core promoter, and one case with double mutations at nucleotide 1837 and 1846 respectively. Also, all HBV precore mutants were combined with wild type HBV sequence. 3. The relationship between HBV precore mutants and HBeAg status revealed that 4 cases from 13 HBeAg positive(30.8%) and 8 from 15 HBeAg negative or Anti-Hbe positive(53.3 %) were mutants. 4. In analysis of the types of mutants and histopathological findings of liver diseases, 6 among 15 chronic active hepatitis(40.0%), all 3 cases with hepatocellular carcinoma(100,0 %), 2 among 4 asymptomatic carriers with minimal histopathologic changes(50.0%) and a case with chronic lobular heaptitis(100.0%) showed precore region mutation. CONCLUSION: The patterns of HBV precore mutants in Korea could be summarized as followings. Firstly, most of the mutations are composed of G to A change at nucleotide 1896. Secondly, the most of the mutants at nuclmtide 1896 have been associated with simultaneous mutations at core promoter, core gene, and rarely at other positions, and manifested usua'ly mixed type viremic conditions. Thirdly, although precore mutation could be occurred in asymptomatic carrier, this type of mutation might be closely related with chronic or severe liver disease. However, it needs further investigations hereafter.

Assessment of Validity of RT-PCR and EIA for The Detection of Hepatitis C Virus Infection / 예방의학회지

This study was conducted to estimate the validity of reverse transcriptase-polymerase chain reaction(RT-PCR) compared to enzyme immunoassay(EIA) for the detection of hepatitis C virus (HCV) infection. ElA for antibody to HCV(anti-HCV) and RT-PCR for HCV was executed on the subjects from Pusan and kyungnam area with questionnaire survey to collect some relating factors of HCV infection As the result from 617 cases, the prevalence of flcv infection was 1.5% by ElA and 3.7% by RT-PCR(p<0.05), and the age standardized rate was 1.7% and 3.4% by ElA and RT-PCR, respectively. The prevalence of hepatitis B surface antigen(HBsAg) was 6.8% by enzyme linked immunosorbent assay(ELlSA) and the age standardized rate was 7.7%. It was the higher in male group comparing to female group(p<0.01). Both of the prevalence of HCV and HBsAg were higher in elevated asparate aminotransferase(AST) and alanine aminotransferase (ALT) group than in normal AST and ALT group(p<0.01). There was no specific risk factor of HCV infection. Though the degree of agreement of EIA and RT-PCR by gamma statistics was 97.2%, it showed a significant difference between the two methods(p<0.01). For the detection of HCV infection, positive predictive value of ElA was 66.7 % and negative predictive value of EIA was 97.2%. This study suggests that negative result to anti-HCV by ElA didn't mean the free state of HCV infection, therefore it would be helpful that further monitoring for HCV infection by RT-PCR in the case of elevated AST and ALT and/or clinically suspected.