Related Experiment Video
Updated: May 15, 2026
09:20
In situ Subcellular Fractionation of Adherent and Non-adherent Mammalian Cells
Published on: July 23, 2010
Human papillomavirus early proteins and apoptosis
Qiong Cai1, Liang Lv, Qian Shao
1Department of Obstetrics and Gynecology, First People's Hospital of Yunnan Province, Kunming 650032, Yunnan, People's Republic of China.
Archives of Gynecology and Obstetrics
|December 25, 2012
Summary
Human papillomavirus (HPV) early proteins E2, E5, E6, and E7 regulate apoptosis, impacting cellular pathways and potentially triggering gynecological diseases in women.
Area of Science:
- Oncology
- Virology
- Cell Biology
Background:
- Human papillomavirus (HPV) early proteins (E2, E5, E6, E7) are implicated in apoptosis regulation.
- These viral proteins interact with host cellular proteins to modulate apoptosis.
- Dysregulation of apoptosis by HPV proteins contributes to disease pathogenesis.
Purpose of the Study:
- To review the literature on HPV early proteins and their role in apoptosis.
- To elucidate the mechanisms by which HPV early proteins interfere with apoptosis.
- To understand the link between HPV-induced apoptosis and gynecological pathologies.
Main Methods:
- Literature search of major scientific databases (e.g., Elsevier).
- Selection criteria included studies on HPV, early proteins, and apoptosis.
- Synthesis of existing research findings.
Main Results:
- HPV oncoprotein E6 inhibits apoptosis via the p53 pathway.
- HPV E5 protein confers protection against tumor necrosis factor-related apoptosis.
- HPV E2 protein regulates viral transcription and apoptosis induction.
- HPV oncoprotein E7 modulates both apoptosis activation and inhibition.
- Full-length HPV E2 proteins control E6/E7 transcription, influencing E6/E7-mediated apoptosis.
Conclusions:
- HPV early proteins (E2, E5, E6, E7) exhibit diverse roles in regulating apoptosis.
- Understanding these regulatory principles is crucial for comprehending HPV pathogenesis.
- Interference with apoptosis by HPV proteins is a key mechanism triggering gynecological diseases in women.
Related Concept Videos
01:31The Intrinsic Apoptotic Pathway
Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
02:28Leaky Scanning
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
01:17The Extrinsic Apoptotic Pathway
The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
01:51Mechanisms of Retrovirus-induced Cancers
Retroviruses are RNA viruses that have been shown to cause cancers in diverse species, including chickens, mice, cats, and monkeys. The RNA genomes of these viruses are first reverse-transcribed into single and then double-stranded DNA (dsDNA) copies. This dsDNA called proviral DNA then integrates into the host genome. Subsequently, the host cell transcribes the proviral DNA in concert with the chromosomal DNA. This leads to the production of viral RNA and proteins that assemble at the host...
01:30Apoptosis
Apoptosis is a combination of two Greek words, 'apo' and 'ptosis,' meaning separation and falling off, respectively. Hippocrates used this word to describe gangrene, which was caused due to bandaging of fractured bones. Apoptosis was distinguished from necrosis in 1970 when John Kerr reported observations of morphological changes occurring during apoptosis. During one experiment, he observed that the disruption of blood supply to the liver tissue resulted in a size reduction of the tissue.
01:24Caspases
Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside cells.