Fig. 8.
Proposed model for the mechanisms of regulation of ESAG9-EQ expression in slender and stumpy forms. In slender forms (left-hand side), a negative regulator (red oval) binds to the element sequence (red bar) in the ESAG9-EQ 3′UTR and causes mRNA degradation of the transcript, repressing the expression of ESAG9-EQ. In stumpy forms (right-hand side), a positive regulator (purple oval) binds to the element sequence, increasing its mRNA abundance. Translation of the transcript also increases, potentially through the association or stabilisation of additional regulators (green circles) that require other sequences in the ESAG9 3′UTR outside the 34 nt element. Combined, these result in the release of gene expression repression in the stumpy lifecycle stage. AAAn: poly(A) tail.