PMID- 8985325
OWN - NLM
STAT- MEDLINE
DCOM- 19970131
LR  - 20200724
IS  - 0022-538X (Print)
IS  - 1098-5514 (Electronic)
IS  - 0022-538X (Linking)
VI  - 71
IP  - 1
DP  - 1997 Jan
TI  - The human T-cell lymphotropic virus type 1 Tof protein contains a bipartite 
      nuclear localization signal that is able to functionally replace the 
      amino-terminal domain of Rex.
PG  - 75-83
AB  - The X region of human T-cell lymphotropic virus type 1 (HTLV-1) encodes two 
      nucleolar/nuclear proteins, the posttranscriptional regulator of mRNA expression 
      Rex and a protein of unknown function named Tof. To gain insight into the 
      possible biological role of Tof, we investigated the mechanism governing its 
      intracellular trafficking and identified its nucleolar/nuclear localization 
      signal (NLS). Mutational analysis of Tof revealed that its NLS was located 
      between amino acids 71 and 98 and contained two arginine-rich domains that 
      functioned in an interdependent manner. Studies of Tof-Rex hybrid proteins showed 
      that the Tof NLS could functionally replace the NLS of Rex at the level of 
      nuclear targeting. As the NLS of Rex is known to mediate its interaction with its 
      RNA target, the Rex-responsive element (RXRE), we tested whether the NLS of Tof 
      could replace that of Rex in mediating activation of a RXRE-containing mRNA. 
      Results showed that the NLS of Tof was indeed able to mediate activation of 
      RXRE-containing mRNAs, suggesting that Tof itself may function as a regulator of 
      RNA expression and utilization. A comparison of their compartmentalization in 
      response to actinomycin D treatment indicated that Tof did not share Rex's 
      shuttling pathway. Expression of Tof from its natural multiply spliced mRNA 
      required the presence of Rex, suggesting that Tof may regulate viral or cellular 
      mRNA expression during the later stages of viral replication.
FAU - D'Agostino, D M
AU  - D'Agostino DM
AD  - Department of Oncology and Surgical Sciences, University of Padua, Italy. 
      dmdago@ipdunidx.unipd.it
FAU - Ciminale, V
AU  - Ciminale V
FAU - Zotti, L
AU  - Zotti L
FAU - Rosato, A
AU  - Rosato A
FAU - Chieco-Bianchi, L
AU  - Chieco-Bianchi L
LA  - eng
GR  - IF32CA60403-01/CA/NCI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Virol
JT  - Journal of virology
JID - 0113724
RN  - 0 (Gene Products, env)
RN  - 0 (Gene Products, rex)
RN  - 0 (Protein Sorting Signals)
RN  - 0 (RNA, Messenger)
RN  - 0 (RNA, Viral)
RN  - 0 (Recombinant Fusion Proteins)
RN  - 0 (Retroviridae Proteins)
RN  - 0 (Retroviridae Proteins, Oncogenic)
RN  - 0 (env Gene Products, Human Immunodeficiency Virus)
RN  - 0 (gp21 protein, Human T-lymphotropic virus 1)
RN  - 0 (tof protein, Human T-lymphotropic virus 1)
RN  - 1CC1JFE158 (Dactinomycin)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Dactinomycin/pharmacology
MH  - Gene Products, env/genetics/metabolism
MH  - Gene Products, rex/genetics/*metabolism
MH  - HeLa Cells
MH  - Human T-lymphotropic virus 1/drug effects/genetics/*metabolism
MH  - Humans
MH  - Molecular Sequence Data
MH  - *Protein Sorting Signals
MH  - RNA, Messenger
MH  - RNA, Viral/metabolism
MH  - Rabbits
MH  - Recombinant Fusion Proteins/genetics/metabolism
MH  - Retroviridae Proteins/chemistry/genetics/*metabolism
MH  - Retroviridae Proteins, Oncogenic/genetics/metabolism
MH  - Subcellular Fractions
MH  - env Gene Products, Human Immunodeficiency Virus
PMC - PMC191026
EDAT- 1997/01/01 00:00
MHDA- 1997/01/01 00:01
PMCR- 1997/01/01
CRDT- 1997/01/01 00:00
PHST- 1997/01/01 00:00 [pubmed]
PHST- 1997/01/01 00:01 [medline]
PHST- 1997/01/01 00:00 [entrez]
PHST- 1997/01/01 00:00 [pmc-release]
AID - 10.1128/JVI.71.1.75-83.1997 [doi]
PST - ppublish
SO  - J Virol. 1997 Jan;71(1):75-83. doi: 10.1128/JVI.71.1.75-83.1997.