TLS Online TPP Program

#Question id: 2978


The most important regulatory control that restricts cyclins to the appropriate cell cycle stage is ubiquitin mediated, proteasome-dependent protein degradation. Which of the following statement is incorrect regarding to the degradation of protein?

#SCPH06 I Botany
  1. SCF and APC/C are multisubunit ubiquitin-protein ligases that belong to the RING finger family of ubiquitin protein ligases which ensure that the cell cycle engine is driven forward and that cells cannot “go backward” in the cell cycle.

  2. SCF recognizes its substrates only when they are phosphorylated.

  3. The substrate specificity of active, dephosphorylated APC/C is determined in part by its association with one of two related substrate targeting factors called Cdc20 and Cdh1.

  4. The substrates of APC/C contain recognition motifs known as destruction box which is lysine rich.