Terminators and introns are vital regulators of gene expression
in many eukaryotes; however, the functional importance
of these elements for controlling gene expression in Agaricomycetes
remains unclear. In this study, the effects of Ceriporiopsis
subvermispora terminators and introns on the expression
of a recombinant hygromycin B phosphotransferase
gene (hph) were characterized. Using a transient transformation
system, we proved that a highly active terminator (e.g.,
the gpd terminator) is required for the efficient expression of
the hph gene. Mutational analyses of the C. subvermispora
gpd terminator revealed that hph expression was dictated by
an A-rich region, which included a putative positioning element,
and polyadenylation sites. In contrast, our results indicated
that introns are not required for the expression of
hph directed by the CsĪ²1-tub and Csgpd promoters in C.
subvermispora. This study provides insights into the functions
and cis-element requirements of transcriptional terminators
in Agaricomycetes, which may be relevant for designing
recombinant genes for this important fungal class.