LCCN

Latency-associated nuclear antigen
File:LANA structure.png Structure of LANA
Identifiers
Symbol	?

Latency-associated nuclear antigen (LANA) is a multifunctional protein encoded by the Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8). LANA plays a crucial role in the maintenance of viral latency and the persistence of the viral genome within infected host cells.

Structure and Function

LANA is a large nuclear protein that is essential for the episomal maintenance of the KSHV genome during latent infection. It is encoded by the ORF73 gene of KSHV and is expressed in all KSHV-infected cells during latency.

Structure

LANA is characterized by several functional domains:

• N-terminal domain: Involved in transcriptional regulation and interaction with host chromatin.
• Central domain: Contains a proline-rich region that is important for protein-protein interactions.
• C-terminal domain: Responsible for binding to the terminal repeat (TR) sequences of the KSHV genome, facilitating episomal maintenance.

Function

LANA has multiple functions that contribute to the viral life cycle:

• Genome tethering: LANA tethers the KSHV episome to host chromosomes, ensuring its segregation during cell division.
• Transcriptional regulation: LANA can act as a transcriptional activator or repressor, modulating the expression of both viral and host genes.
• Immune evasion: LANA interferes with host immune responses, aiding in the persistence of the virus.

Role in Pathogenesis

LANA is implicated in the pathogenesis of KSHV-associated diseases, such as Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman's disease. By maintaining viral latency and modulating host cell functions, LANA contributes to the oncogenic potential of KSHV.

Research and Therapeutic Implications

Understanding the structure and function of LANA is critical for developing therapeutic strategies against KSHV-associated malignancies. Targeting LANA's interactions with host proteins or its ability to maintain viral latency could provide novel approaches for treatment.

Also see

• Kaposi's sarcoma-associated herpesvirus
• Viral latency
• Oncogenic viruses
• Herpesviridae