Inducible Expression System Transcription Modulators Comprising A Distributed Protein Transduction Domain And Methods For Using The Same

Abstract

Aspects of the invention include inducible expression systems in which a transcription modulator having a distributed protein transduction domain is employed. Aspects of the invention further include methods of using the systems to induce expression of a coding sequence, as well as kits that find use in practicing methods of the invention. The systems, components thereof, methods and kits find use in a variety of different applications.

1 . An inducible expression system comprising:
 (a) a host cell comprising an expression cassette comprising:
 (i) a transcription modulator responsive element; 
 (ii) a promoter; and 
 (iii) a coding sequence; and 
   (b) a transcription modulator comprising:   (i) a transcription modulator domain that binds to the transcription modulator responsive element;   (ii) an expression modulatory domain operably linked to the transcription modulator domain; and
 (iii) a distributed protein transduction domain. 
   
     
     
         2 . The expression system according to  claim 1 , wherein the transcription modulator responsive element is a Tet responsive element. 
     
     
         3 . The expression system according to  claim 1 , wherein the transcription modulator domain is a Tet transcription modulator domain. 
     
     
         4 . The expression system according to  claim 3 , wherein the Tet transcription modulator binds to the transcription modulator responsive element in the absence of an expression mediator. 
     
     
         5 . The expression system according to  claim 3 , wherein the Tet transcription modulator binds to the transcription modulator responsive element in the presence of an expression mediator. 
     
     
         6 . The expression system according to  claim 1 , wherein the system further includes an expression mediator. 
     
     
         7 . The expression system according to  claim 6 , wherein the expression mediator is selected from the group consisting of tetracycline and doxycycline. 
     
     
         8 . The expression system according to  claim 1 , wherein the distributed protein transduction domain comprises a basic patch made up 3 or more non-sequential basic amino acid residues. 
     
     
         9 . The expression system according to  claim 8 , wherein the number percentage of basic amino acid residues in the basic patch is 30 or more. 
     
     
         10 . The expression system according to  claim 1 , wherein the expression system further comprises a transduction enhancer. 
     
     
         11 . The expression system according to  claim 10 , wherein the transduction enhancer is a DNA transfection reagent. 
     
     
         12 . A transcription modulator comprising:
 (i) a transcription modulator domain that binds to a transcription modulator responsive element;   (ii) an expression modulatory domain fused to the transcription modulator domain; and
 (iii) a distributed protein transduction domain. 
   
     
     
         13 - 17 . (canceled) 
     
     
         18 . A nucleic acid encoding a transcription modulator comprising:
 (i) a transcription modulator domain that binds to a transcription modulator responsive element;   (ii) an expression modulatory domain fused to the transcription modulator domain; and
 (iii) a distributed protein transduction domain. 
   
     
     
         19 - 23 . (canceled) 
     
     
         24 . A method of inducing expression of a coding sequence in a host cell, the method comprising:
 (a) providing a host cell comprising:
 (i) an expression cassette comprising: a transcription modulator responsive element, a promoter and the coding sequence; and 
 (ii) a transcription modulator comprising: a transcription modulator domain that binds to the transcription modulator responsive element in an expression mediator mediated manner, an expression modulatory domain operably linked to the transcription modulator domain, and a distributed protein transduction domain; and 
   (b) maintaining the host cell under conditions sufficient to induce expression of the coding sequence.   
     
     
         25 . The method according to  claim 24 , wherein the method comprises changing the concentration in the host cell of an expression mediator that mediates binding of the transcription modulator to the transcription modulator responsive element in a manner sufficient to express the coding sequence. 
     
     
         26 . The method according to  claim 24 , wherein the transcription modulator responsive element is a Tet responsive element and the transcription modulator is a Tet regulatory domain. 
     
     
         27 - 29 . (canceled) 
     
     
         30 . The method according to  claim 25 , wherein the expression mediator is selected from the group consisting of tetracycline and doxycycline. 
     
     
         31 . The method according to  claim 24 , wherein the distributed protein transduction domain comprises a basic patch made up 3 or more non-sequential basic amino acid residues. 
     
     
         32 . The method according to  claim 31 , wherein the number percentage of basic amino acid residues in the basic patch is 30 or more. 
     
     
         33 . The method according to  claim 24 , wherein the method further comprises contacting the host cell with a transduction enhancer. 
     
     
         33 - 46 . (canceled)