Cloning, Expression Of L1, E7 And L1-E7 Genes Of HPV 16 And A Cell, Molecular Biological Research For The Virus-like Particle Vaccine And Their Function

Papillomaviruses are nonenveloped particles characterized by an icosahedral capsid with a diameter of about 50 nm. The capsid is composed of 72 pentameric capsomeres constituted of the L1 protein. The L1 polypeptide represents about 90% of the protein content of viral particles and has an apparent molecular weight of 54-58 kDa. Viral capsid contains also a minor polypeptide, designated L2, with an apparent molecular weight of 68-76 kDa. Viral genome is a double-stranded, circular, and covalently closed DNA molecule of 7500-8000 base pairs (bp). The viral genome can be divided into three parts: (1) a noncoding region, the long control region (LCR) or upstream regulatory region, corresponding to 7-11% of the genome length; (2) the early (E) region (about 50% of the genome length) encoding proteins involved in cell transformation (E6, E7, E5), or in the replication and transcription of viral genome (E1, E2); and (3) the late (L) region, which encodes the major L1 and minor L2 capsid proteins.Epidemiological studies showed that HPV 16 is mainly transmitted by sexually...