• 정보처리학회논문지C
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• 제17C권1호
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• pp.37-46
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• 2010

IPTV 시스템에서 콘텐츠 및 서비스 제공자의 권익보호는 수신제한시스템(CAS, Conditional Access System) 및 디지털저작권관리(DRM, Digital Right Management)를 통해서 이루어진다. 특히 CAS의 경우, 계층화된 인증키를 사용하여 권한이 있는 사용자에게만 암호화된 콘텐츠를 복호화할 수 있도록 한다. 하지만 CAS가 콘텐츠 제공자와 스마트카드(SC, Smart Card) 사이 구간만의 보안을 제공하기 때문에 셋톱박스(STB, Set-Top Box)와 SC 간 보호 받지 못하는 채널을 도청하는 McCormac Hack 공격이나 SC 복제 공격으로부터 시스템을 보호할 수 없다. 본 논문에서는 McCormac Hack 공격뿐 만 아니라 SC 복제 공격에도 강건하면서 다중 STB를 지원할 수 있는 SC / STB 인증 기법을 제안한다. SC 복제 공격을 막기위해 SC등록 단계에서 STB와 SC를 바인딩하였던 기존 기법은 다중 STB환경을 지원하지 못한다. 제안하는 시스템은 가입자관리시스템에서 STB 정보를 IPTV의 양방향 채널 특성을 이용하여 동적으로 갱신함으로서 사용자의 다중 STB를 효과적으로 지원한다.

• KSBB Journal
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• 제22권4호
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• pp.179-184
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• 2007

본 연구는 특정 아미노산들로 구성된 단위체가 반복되는 형태를 가지는 반복단위 단백질을 유전공학적으로 합성하는 방법들과 응용사례들을 소개하고 있다. 유전공학적 합성법은 단위체의 반복횟수를 정확하게 제어하면서 인식부위의 제한을 없애서 원하는 단백질만을 발현할 수 있도록 발전해왔으며, 최근 소개된 RDL과 CCM 방법에 의하여 가능해졌다. 반복단위 단백질의 응용사례로는 대표적으로 ELP, SLP, Prolamin 등의 단백질을 합성하여 생체재료나 약물전달시스템을 개발하는데 응용하거나, ELFSE의 drag-tag 개발에 응용되는 연구들이 진행되고 있다. 화학적으로 합성된 고분자에 비해 유전공학적으로 합성된 반복단위 고분자의 경우, 고유의 물리적 성질과 함께 환경에 미치는 유해함이 상대적으로 적다는 점 때문에 미래의 신소재로 기대되고 있다.

• Journal of Plant Biotechnology
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• 제7권1호
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• pp.51-55
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• 2005

Many cloning vectors in which cDNAs can be inserted to the sense orientation have been developed. Uni-ZAP XR vector (Stratagene) should contain clones that are oriented to sense direction with respect to T3 RNA polymerase primer. Unexpectedly, large portions of cDNAs in Chinese cabbage cDNA library showed unusual insertions, antisense orientation and a hybrid of two different clones. Using two clones, 4H03 and 53-B10, derived from different cDNA libraries, we proposed and demonstrated the possibility of unusual-construct formation by in vitro translation and northern blot analysis. The 4H03 clone was inserted with inverse direction, and its transcript and translation product could be produced by T7 RNA polymerase, indicating that this clone is definitely inserted into inverse orientation. The 53-B10 that contains two independent genes was turned out to be a hybrid in which two genes are inserted to opposite direction each other. All unusual constructs might be due to the presence of small fragments of DNA, like adapter. However, the mechanism underlined the formation of unusual constructs is still remain to be solved.

• The Plant Pathology Journal
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• 제26권1호
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• pp.25-31
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• 2010

Papaya ringspot virus (PRSV) causes the most widespread and devastating disease in papaya. Isolates of PRSV originating from different geographical regions in south India were collected and maintained on natural host papaya. The entire coat protein (CP) gene of Papaya ringspot virus-P biotype (PRSV-P) was amplified by RTPCR. The amplicon was inserted into pGEM-T vector, sequenced and sub cloned into a bacterial expression vector pRSET-A using a directional cloning strategy. The PRSV coat protein was over-expressed as a fusion protein in Escherichia coli. SDS-PAGE gel revealed that CP expressed as a ~40 kDa protein. The recombinant coat protein (rCP) fused with 6x His-tag was purified from E.coli using Ni-NTA resin. The antigenicity of the fusion protein was determined by western blot analysis using antibodies raised against purified PRSV. The purified rCP was used as an antigen to produce high titer PRSV specific polyclonal antiserum. The resulting antiserum was used to develop an immunocapture reverse transcription-polymerase chain reaction (IC-RT-PCR) assay and compared its sensitivity levels with ELISA based assays for detection of PRSV isolates. IC-RT-PCR was shown to be the most sensitive test followed by dot-blot immunobinding assay (DBIA) and plate trapped ELISA.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.167-171
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• 2004

We constructed an oligo-d(T) primed directional cDNA library from the Bombyx mandarina whole larvae. In an effort to isolate genes expressed in the B. mandarina, 227 expressed sequence tags (ESTs) were generated by single-pass sequencing from the cDNA library. Sequence analysis showed that 107 clones (47.1%) were classified into known genes and 120 clones (52.9%) were novel transcripts, which are unknown for their function. Of the 107 known genes, the most abundant gene was found to be actin and followed by serine protease in the expression profile. Among these clones, a serine protease homolog (BmSP) which is a class of proteolytic enzymes isolated. Full-length sequence of the BmSP cDNA clone was 922 bp in length and has an open reading frame of 276 amino acids. The conserved histidine, aspatic acid and serine residues forming the catalytic center as well as cysteine residues contributing to three disulphide bonds also were found in Bmsp gene. mRNA expression analysis revealed a high and specific expression of the gene only in midgut tissue, suggesting that BmSP gene is closely associated with the expression of digestive enzyme.