Epstein–Barr virus latent membrane protein 1 (LMP1) is an

Epstein–Barr virus The Epstein–Barr virus (EBV), also known as human herpesvirus 4 (HHV-4), is one of the nine known Herpesviridae#Human herpesvirus types, human herpesvirus types in the Herpesviridae, herpes family, and is one of the most common viruses in ...

(EBV) protein that regulates its own expression and the expression of human genes. It has a

molecular weight A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...

of approximately 63

kDa The dalton or unified atomic mass unit (symbols: Da or u, respectively) is a unit of mass defined as of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. It is a non-SI unit accepted f ...

, and its expression induces many of the changes associated with EBV infections and activation of primary

B cell B cells, also known as B lymphocytes, are a type of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or inserted into the plasm ...

s. LMP1 is the best-documented

oncoprotein An oncogene is a gene that has the potential to cause cancer. In tumor cells, these genes are often mutated, or expressed at high levels.

of the EBV latent

gene product A gene product is the biochemical material, either RNA or protein, resulting from the expression of a gene. A measurement of the amount of gene product is sometimes used to infer how active a gene is. Abnormal amounts of gene product can be corre ...

s, as it is expressed in most EBV-related human cancers such as the various malignant Epstein-Barr virus-associated lymphoproliferative diseases. The structure of LMP1 consists of a short cytoplasmic terminal tail, six trans-membrane domains, and a long

cytoplasm The cytoplasm describes all the material within a eukaryotic or prokaryotic cell, enclosed by the cell membrane, including the organelles and excluding the nucleus in eukaryotic cells. The material inside the nucleus of a eukaryotic cell a ...

C-terminus The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, carboxy tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein Proteins are large biomolecules and macromolecules that comp ...

, which contains three activating domains: CTARt, CTAR2, and CTAR3. Each CTAR domain contains an amino acid sequence that serves as a recognition site for cellular adaptors to bind and trigger a series of

signal transduction pathway A signal is both the process and the result of transmission of data over some media accomplished by embedding some variation. Signals are important in multiple subject fields including signal processing, information theory and biology. In ...

s that can lead to a change in

gene expression Gene expression is the process (including its Regulation of gene expression, regulation) by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, proteins or non-coding RNA, ...

. LMP-1 is a functional homologue of

tumor necrosis factor Tumor necrosis factor (TNF), formerly known as TNF-α, is a chemical messenger produced by the immune system that induces inflammation. TNF is produced primarily by activated macrophages, and induces inflammation by binding to its receptors o ...

and mediates signaling through the nuclear factor-κB pathway, mimicking

CD40 Cluster of differentiation 40, CD40 is a type I transmembrane protein found on antigen-presenting cells and is required for their activation. The binding of CD154 (CD40L) on T helper cell, TH cells to CD40 activates antigen presenting cells and i ...

receptor signaling. It is often found in the malignant

Reed–Sternberg cell Reed–Sternberg cells (also known as lacunar histiocytes for certain types) are distinctive, giant cells found with light microscopy in biopsies from individuals with Hodgkin lymphoma. They are usually derived from B lymphocytes, classicall ...

s of

Hodgkin lymphoma Hodgkin lymphoma (HL) is a type of lymphoma in which cancer originates from a specific type of white blood cell called lymphocytes, where multinucleated Reed–Sternberg cells (RS cells) are present in the lymph nodes. The condition was named a ...

, the malignant

s of EBV-associated B cell lymphatic cancers, and the malignant

NK cells Natural killer cells, also known as NK cells, are a type of cytotoxic lymphocyte critical to the innate immune system. They are a kind of large granular lymphocytes (LGL), and belong to the rapidly expanding family of known innate lymphoid cell ...

of NK/T cell lymphatic cancers.

References

{{DEFAULTSORT:Epstein-Barr virus latent membrane protein 1 Viral structural proteins Epstein–Barr virus