Vectors and methods for tissue specific synthesis of proteins in eggs of transgenic hens

Abstract

Vectors and methods are provided for introducing genetic material into cells of a chicken or other avian species. More particularly, vectors and methods are provided for transferring a transgene to an embryonic chicken cell, so as to create a transgenic hen wherein the transgene is expressed in the hen's oviduct and the transgene product is secreted in the hen's eggs and/or those of her offspring. In a preferred embodiment, the transgene product is secreted in the egg white.

1 . A replication-defective retroviral vector comprising:
 a) a transgene; and   b) control elements operatively-linked to the transgene and capable of directing synthesis of the transgene product in avian egg white, wherein the control elements comprise a promoter, a 5′ untranslated region and a signal sequence.   
     
     
         2 . The vector of  claim 1 , wherein the replication-defective retroviral vector is derived from REV-A. 
     
     
         3 . The vector of  claim 1 , wherein the promoter is chosen from the group consisting of the ovalbumin, lysozyme, conalbumin and ovomucoid promoters, and combinations thereof. 
     
     
         4 . The vector of  claim 1 , wherein the avian is a chicken. 
     
     
         5 . The vector of  claim 1 , wherein the control elements further comprise an enhancer. 
     
     
         6 . The vector of  claim 3 , wherein the promoter comprises an ovalbumin promoter. 
     
     
         7 . The vector of  claim 5 , wherein the enhancer comprises a steroid hormone response element. 
     
     
         8 . The vector of  claim 5 , wherein the enhancer is a viral enhancer. 
     
     
         9 . The vector of  claim 8 , wherein the enhancer is a portion of SV40. 
     
     
         10 . A replication-defective retroviral vector comprising:
 a) a transgene; and   b) control elements operatively-linked to the transgene and capable of directing synthesis of the transgene product in avian egg yolk, wherein the control elements comprise a promoter, a 5′ untranslated region, a signal sequence and an uptake sequence.   
     
     
         11 . The vector of  claim 10 , wherein the replication-defective retroviral vector is derived from REV-A. 
     
     
         12 . The vector of  claim 10 , wherein the promoter is chosen from the group consisting of the vitellogenin and apolipoprotein A promoters, and combinations thereof. 
     
     
         13 . The vector of  claim 10 , wherein the avian is a chicken. 
     
     
         14 . The vector of  claim 10 , wherein the control elements further comprise an enhancer. 
     
     
         15 . The vector of  claim 14 , wherein the enhancer comprises a steroid hormone response element. 
     
     
         16 . The vector of  claim 14 , wherein the enhancer is a viral enhancer. 
     
     
         17 . The vector of  claim 16 , wherein the enhancer is a portion of SV40. 
     
     
         18 . A method for transferring a transgene to an embryonic chicken cell, comprising the step of introducing a replication-defective retroviral vector into the cell, wherein the vector comprises the transgene and control elements operatively-linked thereto and capable of directing the synthesis of the transgene product in egg white, wherein the control elements comprise a promoter, a 5′ untranslated region and a signal sequence. 
     
     
         19 . The method of  claim 18 , wherein the replication-defective retroviral vector is derived from REV-A. 
     
     
         20 . The method of  claim 18 , wherein the control elements further comprise an enhancer.