crystallins

Lens crystalins come in a number of flavors, but there are some taxon specific lens crystallins that are specific to certain groups of organisms.

Vacuity of ID: Comments on Irreducible Complexity - The Panda's Thumb 2006

Some taxon specific crystallins are the result of duplicated genes.

Vacuity of ID: Comments on Irreducible Complexity - The Panda's Thumb 2006

We believe that greater consideration should be given to the possibility that enzyme/crystallin recruitment is, in general, an adaptive process and that enzyme/crystallins may provide specific benefits to the lens.

Vacuity of ID: Comments on Irreducible Complexity - The Panda's Thumb 2006

Many taxon specific crystallins are encoded in a single gene which produce both an enzyme and the lens crystallin.

Vacuity of ID: Comments on Irreducible Complexity - The Panda's Thumb 2006

If ID has a better mechanism for the occurrence of the taxon specific crystallins and the implications of their distributions i.e. bird/reptile LDHB crystallin, then I would like to hear it.

Vacuity of ID: Comments on Irreducible Complexity - The Panda's Thumb 2006

So there are examples of taxon specific crystallins that are recruited from metabolic enzymes by the addition of a lens specific promoter.

Vacuity of ID: Comments on Irreducible Complexity - The Panda's Thumb 2006

As has been suggested for other cases 1, 2, the primary selective pressure for this gene recruitment may have been the modification of the optical properties of the lens in an ancestor of elephant shrews, “diluting” the specialized g-crystallins, to help make a softer accommodating lens.

Vacuity of ID: Comments on Irreducible Complexity - The Panda's Thumb 2006

Bloemendal H, de Jong W, Jaenicke R, Lubsen NH, Slingsby C, et al. (2004) Ageing and vision: structure, stability and function of lens crystallins.

PLoS ONE Alerts: New Articles Line Kessel et al. 2010

Interestingly, however, in this case the lens crystallins are known to be made from unrelated proteins, and so by the authors 'criteria there would be no' convergence 'here, even though in the classical definition (see below) this difference would be a crucial fact of convergence, almost diagnostic of the concept.

ScreenTalk 2009

Interestingly, however, in this case the lens crystallins are known to be made from unrelated proteins, and so by the authors 'criteria there would be no' convergence 'here, even though in the classical definition (see below) this difference would be a crucial fact of convergence, almost diagnostic of the concept.

ScreenTalk 2009