Answer
HIV (Human immunodeficiency virus) is a causative agent of a dreadful sexually transmitted disease (STD) called AIDS (Acquired immunodeficiency syndrome). HIV has single-stranded RNA (ribonucleic acid) as a genome, it express a special enzyme called Reverse Transcriptase (RT) and the RT is used for the replication of HIV genome in the host cell (T-lymphocyte). The term central dogma of molecular biology is defined as the expression of a gene in a regulated manner by comprising of replication, transcription and translation. The replication of DNA takes place in interphase (S-phase) of cell cycle. DNA replication results in the formation of two new DNA helices. The semiconservative pattern of DNA replication is demonstrated by Meselson and Stahl. In this, each strand of parent DNA act as template for the new strand, thus producing two new DNA strands. So, the newly formed DNA contains one old strand and one new strand. The enzyme The DNA polymerase is necessary to add nucleotides to the growing strand and this is initiated by a primer in DNA replication. Transcription is the synthesis of RNA (ribonucleic acid) under the direction of DNA. The process of transcription starts with RNA polymerase, this enzyme binds to the sigma factor and in this form; it can recognize the promoter sites in the DNA and is transcribed into RNA. During protein synthesis, mRNA is synthesized under the direction of DNA. The message carried by the DNA is read by the mRNA, this process is called "transcription," it takes place in the nucleus. This mRNA then carries the information to the tRNA and rRNA, which translate the genetic code into proteins, this process is called "translation" and this takes place in the cytoplasm (ribosomes). In contrast to the Crick's central dogma, retrovirus such as HIV (human immune deficiency virus) reproduces in a different way, as they contain reverse transcriptase enzyme. In this, a complementary DNA is transcribed from the RNA genome, and it is called as DNA provirus. The DNA provirus is expressed in the host to produce virions. So, retro viruses replicate by using DNA intermediates.
Work Step by Step
HIV (Human immunodeficiency virus) is a causative agent of a dreadful sexually transmitted disease (STD) called AIDS (Acquired immunodeficiency syndrome). HIV has single-stranded RNA (ribonucleic acid) as a genome, it express a special enzyme called Reverse Transcriptase (RT) and the RT is used for the replication of HIV genome in the host cell (T-lymphocyte). The term central dogma of molecular biology is defined as the expression of a gene in a regulated manner by comprising of replication, transcription and translation. The replication of DNA takes place in interphase (S-phase) of cell cycle. DNA replication results in the formation of two new DNA helices. The semiconservative pattern of DNA replication is demonstrated by Meselson and Stahl. In this, each strand of parent DNA act as template for the new strand, thus producing two new DNA strands. So, the newly formed DNA contains one old strand and one new strand. The enzyme The DNA polymerase is necessary to add nucleotides to the growing strand and this is initiated by a primer in DNA replication. Transcription is the synthesis of RNA (ribonucleic acid) under the direction of DNA. The process of transcription starts with RNA polymerase, this enzyme binds to the sigma factor and in this form; it can recognize the promoter sites in the DNA and is transcribed into RNA. During protein synthesis, mRNA is synthesized under the direction of DNA. The message carried by the DNA is read by the mRNA, this process is called "transcription," it takes place in the nucleus. This mRNA then carries the information to the tRNA and rRNA, which translate the genetic code into proteins, this process is called "translation" and this takes place in the cytoplasm (ribosomes). In contrast to the Crick's central dogma, retrovirus such as HIV (human immune deficiency virus) reproduces in a different way, as they contain reverse transcriptase enzyme. In this, a complementary DNA is transcribed from the RNA genome, and it is called as DNA provirus. The DNA provirus is expressed in the host to produce virions. So, retro viruses replicate by using DNA intermediates.
