Most of the primers used in this study for human or mouse FS, a, pA, and pB inhibin/activin subunits, the four activin receptor subtypes, and p-actin were previously described and demonstrated to provide single, specific PCR bands whose identities were confirmed by Southern blotting or direct sequencing. The sequences of primers not previously utilized are listed in Table 1, and their PCR products’ identities were verified by subcloning (TA cloning kit; Invitrogen, San Diego, CA) and sequencing. A cDNA fragment of human growth-differentiation factor-9 (GDF9; ) was cloned and sequenced by amplifying human oocyte cDNA with the mouse primers. The human-specific primer set (Table 1) was positioned within this fragment.
The FS primer set was designed to detect both alternatively spliced forms of FS; however, only FS315 was significantly amplified when both transcripts were present, although individual cDNAs of either form were successfully amplified. Thus, our results are reported as FS315. proventil inhaler
All experiments included reactions in which the RT enzyme or cDNA template was omitted to eliminate the possibility of amplification from genomic DNA or contaminating template, and most primer sets crossed introns.