Early promotor

The potential usefulness of elfamycins as growth promotors and feed-conversion enhancers is now generally recognized. Low original fermentation yields and difficulties in yield improvements discouraged early attempts to develop aurodox (1, R = CH ) and mocimycin (kirromycin) (1, R = H) commercially. 

In another experiment where overexpression of the C-100 fragment was driven by the JC viral early region promotor (a human papovirus with brain-specific tissue tropism), brain specific expression of mRNA from the transgene was also detected and increased Afi immunoreactivity occurred although no Afi deposits were observed [44]. Expression of the isoform APP-695 under control of the metallothionein promotor led to impaired spatial memory without neuropathological abnormalities [45]. 

---