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"Latar Belakang: APOBEC3G, apolipoprotein B mRNA-editing enzyme, catalytic polypeplidelike JG, merupakan protein manusia yang dapat mengganggu replikasi HIV dengan memasukkan dirinya ke dalam partikel virus dan merusak susunan materi genetik virus. Beberapa studi terbaru menunjukkan bahwa APOBEC3G manusia mengatur infektivitas HIV-1 dengan mendeaminasi dC menjadi dU pada rantai minus DNA yang baru dibentuk, menyebabkan hipermutasi G menjadi A dari rantai plus DNA viral.Induksi hlpermutasi oleh APOBEC3G dapat menyebabkan pembentukan stop kodon pada ORF protein virus dan memicu degradasi DNA virus oleh glikosilase DNA urnsil yang selanjutuya dapat menghambat replikasi HIV. Protein ini layak untuk diteliti lebih lanjut dalam rangka pengembangan anti retrovirus yang berbasis pacta mekanisme penghambatan replikasi HIV-1 melalui jalur APOBEC3G. Sebagai langkab awal, diperlukan sistem ekspresi gen APOBEC3G yang akan diperoleh melalui sintesis dan kloning gen APOBEC3G ke dalam vektor ekspresi DNA rekombinan.Metode: Untuk mendapatkan mRNA APOBEC3G yang akan digunakan sebagai pola cetak dalam sintesis eDNA APOBEC3G, dilalkukan ekstraksi RNA dari sel CEM-GFP menggunakan Rneasy Mini Kit. Agar DNA APOBEC3G lengkap dapat diperoleh dengan lebih mudah, sintesis DNA serat ganda APOBEC3G menggunakan reaksi RT-PCR dua tahap, dibagi atas tiga daerah pada gen APOBEC3G dengan susunan nukleotida yang bertumpang tindih (overlapping) pada bagian ujung segmen DNA yang akan berfungsi sebagai penyambung fragmen-fragmen tersebut menjadi DNA APOBEC3G utub.Hasil: Hasil eksperimen menunjukloan ketiga fragmen APOBEC3G yang masing-masing berukuran 452 pb, 458 pb,dan 433 pb berhasil dibentuk lewat reaksi PCR dengan menggunakan enzim Pfx dan diklona ke dalam vektor plasmid.Kesimpulan: DNA APOBEC3G yang dibagi menjadi 3 fragmen telah berhasil didapat dan terklona ke dalam pBluescript KS (-). Pekerjaan lanjutan akan dilakukan untuk verifikasi sekuen fragmen-fragmen terklona dan menyambung ketiga fragrnen tersebut menjadi DNA APOBEC3G yang utub yang kemudian akan diklona ke dalam vektor ekspresi.

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Background: APOBEC3G, apolipoprotein B rnRNA-cditing enzyme, catalytic polypeptide-like JG,is a human protein that interferes with the replication of HIV by incorporating itself into virus particles and damaging the genetic material of the virus. Several recent studies revealed that human APOBEC3G regulates HIVI infectivity by dearninating dC to dU in the newly synthesized minus strand DNA, resulting in G to A hypermutation of the viral plus strand DNA.Hypermutation induced by APOBEC3G may result in the introduction of stop codons in viral protein open reading frame and degradation of viral DNA by ura<:il-DNA glyoosylase, therefore blocking HlV replication. This protein is therefore suitable for further investigation for the development of ARV (AntiRetroviral) that is based on mechanism of blocking HIV-1 replication inhibition by APOBEC3G through the pathway. In order to obtain the APOBEC3G protein, an expression system of the APOBEC3G gene is required, which will be obtained by synthesis and cloning of the APOBEC3G gene into an expression vector.Method: To obtain the APOBEC3G mRNA that will be used as template for synthesis of APOBEC3G eDNA by RT-PCR using Omniscript enzyme, we performed RNA extraction from CEM-GFP cell line using the Rneasy Mini !Gt. In order to facilitate the synthesis of a complete APOBEC3G DNA, the APOBEC3G DNA double stranded was divided into three regions with overlapping nucleotide sequences at the DNA ends that function in the joining of the fragments into a full length APOBEC3G DNA.Results: The result of the experiments showed that the three fragments of APOBEC3G gene of 452 bp, 458 bp, and 433 bp, were successfully produced by PCR reaction using Pfx enzyme, and cloned into plasmid vector.Conclusions: APOBEC3G DNA that was divided into three fragments has been obtained and cloned illlo Bluescript KS (-) vector. Further study, will be performed to verifY the cloned fragments, and to fuse the fragments into a complete APOBEC3G DNA that will be cloned into an expression vector."

"This thesis presents a novel coarse-grained model of DNA, in which bases are represented as rigid nucleotides. The model is shown to quantitatively reproduce many phenomena, including elastic properties of the double-stranded state, hairpin formation in single strands and hybridization of pairs of strands to form duplexes, the first time such a wide range of properties has been captured by a coarse-grained model. The scope and potential of the model is demonstrated by simulating DNA tweezers, an iconic nanodevice, and a two-footed DNA walker. The first time that coarse-grained modelling has been applied to dynamic DNA nanotechnology."

"From the Publisher: John Butler, bestselling author of Forensic DNA Typing, now applies his expertise on the subject of DNA analysis into an introductory textbook. Fundamentals of Forensic DNA Typing walks students step-by-step through the DNA analysis process beginning with collection of evidence at a crime scene to the statistical interpretation of the results. Also included are brief discussions of such news worthy topics as victim identification from the September 11, 2001 attacks, the identification of the remains of the Romano vs, the last Russian Royal family, and the O.J. Simpson case. New applications, such as genetic genealogy and tracing domestic pet hairs to perpetrators, are also detailed. With its clear and understandable style and extensive list of online ancillaries and study aids, this textbook will make the subject accessible to students in forensic science courses worldwide. Includes a glossary with over 400 terms for quick reference of unfamiliar terms as well as an acronym guide to decipher the DNA dialect; Continues in the style of Forensic DNA Typing, 2e, with high-profile cases addressed in D.N.A. Boxes. "Data, Notes & Applications" sections throughout; Ancillaries include: instructor manual Web site, with tailored set of 1000+ PowerPoint slides (including figures), links to online training websites and a test bank with key."

"DNA topoisomerases represent an essential family of DNA processing enzymes and a large number of topoisomerase inhibitors are used clinically for the treatment of various human cancers. Novels drugs are in clinical development both against type I and type II topoisomerases. The book will include basic biochemical and structural reviews for the cancer-relevant topoisomerases. It will describe how topoisomerase dysfunctions can damage the genome and increase the risk of cancers, and the involvement of topoisomerases in programmed cell death. The book will also present the various topoisomerase inhibitors in clinical use and development and their molecular and cellular mechanisms of action."