SAFB Like Transcription Modulator (SLTM)

SLTM is localized to the cell nucleus, but excluded from nucleoli. SLTM has a punctate distribution and it does not co-localize with SR proteins. SLTM suppressed the ability of oestrogen to activate a reporter gene in MCF-7 breast-cancer cells, inhibition of a constitutively active b-galactosidase gene suggested that this was primarily the consequence of a generalized inhibitory effect on transcription. SLTM induced apoptosis in a range of cultured cell lines. Thus the inhibitory effects of SLTM on gene expression appear to result from generalized down-regulation of mRNA synthesis and initiation of apoptosis consequent upon overexpressing the protein. While indicating a crucial role for SLTM in cellular function, these results also emphasize the need for caution when interpreting phenotypic changes associated with manipulation of protein expression levels.