       Document 0644
 DOCN  M9440644
 TI    Two distinct regions form a functional activation domain of the HTLV-1
       trans-activator Tax1.
 DT    9404
 AU    Tsuchiya H; Fujii M; Tanaka Y; Tozawa H; Seiki M; Department of
       Molecular Virology and Oncology, Kanazawa; University, Japan.
 SO    Oncogene. 1994 Jan;9(1):337-40. Unique Identifier : AIDSLINE
       MED/94134436
 AB    Tax1 of human T-cell leukemia virus type 1 (HTLV-1) is an enigmatic
       viral transactivator that regulates expression of the viral gene and
       also several cellular genes normally controlled by various mitogenic
       signals. However, previous studies have failed to define the functional
       domains of Tax1 for enhancer specificities and for transcriptional
       activation (95% of the protein portion was indispensable for the
       activation function). This complexity has hampered understanding of the
       molecular basis of Tax1 action. In this study, we analysed the
       activation function of a Tax1 fused to the heterologous DNA-binding
       domain of the yeast transcription factor GAL4 and dissected the domain
       required for the activation function by using derivatives of a Tax1
       mutant with an insertion between amino acids (a.a.) 170 and 171.
       Analysis of the derivatives of the mutant fusion protein having various
       partial overlaps encompassing the interrupted site suggested that two
       contiguous stretches, AD-I (2-255 a.a.) and AD-II (227-337 a.a.), should
       be both intact for the activation function of Tax1 and that they form a
       functional activation domain.
 DE    Animal  Base Sequence  Fungal Proteins/PHYSIOLOGY  Gene Products,
       tax/CHEMISTRY/*PHYSIOLOGY  Mice  Molecular Sequence Data
       Structure-Activity Relationship  Support, Non-U.S. Gov't
       *Trans-Activation (Genetics)  3T3 Cells  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

