Table 1 

Mathematical definition of factor activity classification in the NODE model 

sign(a_{gt,[t, e]}) 
sign(d[eve]/dt) 



Type I Repression 
 
 


Type II Repression 
 
+ 


Type I Activation 
+ 
+ 


Type II Activation 
+ 
 


Without loss of generality, we consider the factor activity of GT on eve, as described by Equation 4. The classification is dependent on the mathematical sign of the coefficient of the model a_{gt,[t, e] }and the mathematical sign of the change in eve mRNA d[eve]/dt, and it is different for each factor concentration x[t, e]. A positive (negative) sign is denoted with the "plus" ("minus") symbol "+" (""). 

Aswani et al. BMC Bioinformatics 2010 11:413 doi:10.1186/1471210511413 