Actually, I have purified a protein from plant material
of a true fern. From the pure protein a lot of its sequence
information has been obtained after tryptic digestion and
N-terminal sequence analysis of the resulting peptides
(about 70-80 % of the proteins amino acid sequence has been
determined).
By use of these amino acid sequences degenerative primers have
been deduced and pairs of primers from different peptides have
been used for PCR together with genomic DNA (after hundreds of
runs no meaningful PCR products have been obtained).
Until mow, the overexpression of only one recombinant fern
protein is described in literature and RNA was used (instead of
DNA) for construction of a cDNA library following PCR with
degenerative primers.
Does someone know is there a special intron or exon problem with
genomic DNA from fern species ?
Is the codon usage of this "fossil" plant family much different
to angiosperms or other organisms and the reason for the
problems ?
Any hints, help or comments to this problem is welcome.
Best regards,
Andreas Giessauf, PhD
Institut für Chemie
Universität Graz
