tat

tat

noun, often capitalized \ˈtat\

Definition of TAT

1

: a small protein produced by a lentivirus (as HIV) within infected cells that greatly increases the rate of viral transcription and replication and that is also secreted extracellularly where it plays a role in increasing viral replication in newly infected cells and in enhancing the susceptibility of T cells to infection—called also tat protein

2

: the viral gene that codes for the tat protein