0:03
Another class of components
of the humoral innate immunity
is represented by pentraxins.
And here, I will focus my attention
on pentraxin 3, PTX3.
PTX3 was originally cloned
in a gene fishing expedition
as in IL-1, or LPS,
or TNF inducible gene.
0:26
This slide is a schematic
representation
of the extraction of PTX3,
its genomic organization,
transcript, and protein.
And the molecule was cloned by us.
And we cloned a mouse
and the human cDNA in genomic
and characterized the promoter.
PTX3 is a soluble protein
consisting of a pentraxin domain
encoded by the third exon,
coupled with an unrelated
and terminal portion.
The model here suggests
the pentraxin domain
holds with a jelly-roll type
of the topology.
As other pentraxins,
PTX3 forms multimers,
but in contrast
to the classic short pentraxins,
which form a pentamer,
PTX3 is organized as an octamer.
And intra and inter-chain
disulfide bridges
play a key role in the multimeric
organization of PTX3.
1:21
The pentraxin domain of PTX3
is related to the
classic short pentraxins,
which include the C-reactive protein
and the serum amyloid P component.
C-reactive protein is a classic
acute phase protein in humans.
We were lucky
because we cloned the first member
of the long pentraxin family
in which a pentraxin domain
is coupled with unrelated
and terminal portions.
This slide emphasizes, in particular,
that we recently cloned
another member of the family
in silico, in physical,
that we called PTX4.
This slide also shows
an evolution of the analysis
of the pentraxin superfamily,
indicating that pentraxins
are ancient in evolution.
On the right side, one can see
the toll fish and drosophila.
And that the mother
of all pentraxins
was most likely a long pentraxin.
