Constitutively active Ras proteins (RasD) 

Replacement of the normal glycine 12 with any other amino acid (except proline) blocks the functional binding of GAP proteins and in essence “locks” Ras in the active GTP-bound state.

TLS Online TPP Program

#Id: 2733

#Unit 12. Applied Biology

For the generation of transgenic plant in crop improvement, one important regulatory gene ‘X’ was overexpressed in a crop plant. Out of 30 transgenic rice plants generated, 22 showed high levels of gene ‘X’ expression. However, rest 8 lines displayed low level of expression. One explanation of such observation may be: 

Suppression effect of the transgene 

Knock down effect of gene X 

Gene silencing effect 

Co-suppression effect of transgene

 

TLS Online TPP Program

#Id: 2734

#Unit 12. Applied Biology

Cultivation of transgenic plants for the recovery of pharmaceutical compounds (medicines) is popularly known as 'pharming';

TLS Online TPP Program

#Id: 6162

#Unit 12. Applied Biology

TLS Online TPP Program

#Id: 6163

#Unit 12. Applied Biology

Insect-resistant transgenic crops were first commercialized in the mid-1990s with the introduction of GM corn (maize), potato and cotton plants expressing genes encoding the entomocidal δ-endotoxin from Bacillus thuringiensis.

TLS Online TPP Program

#Id: 6164

#Unit 12. Applied Biology

The first commercial Bt cotton variety was released in USA by Monsanto (Bollgard), which contains Cry 1Ac gene of Bacillus thuringiensis. (first generation Bt-cotton)

TLS Online TPP Program

#Id: 6165

#Unit 12. Applied Biology

Second generation of improved Bt-cotton with two Bt-genes, now designated Bollgard II.  Bollgard II cotton contains Cry 1 A(c) and Cry II A(b).