Amino acid sequences of lower vertebrate parvalbumins and their evolution: parvalbumins of boa, turtle, and salamander.

Abstract

One major parvalbumin each was isolated from the skeletal muscle of two reptiles, a boa snake, Boa constrictor, and a map turtle, Graptemys geographica, while two parvalbumins were isolated from an amphibian, the salamander Amphiuma means. The amino acid sequences of all four parvalbumins were determined from the sequences of their tryptic peptides, which were ordered partially by homology to other parvalbumins. Phylogenetic study of these and 16 other parvalbumin sequences revealed that the turtle parvalbumin belongs to p lineage, while the salamander sequences belong, one each, to the a and p lineages defined by Goodman and Pechire ( 1977). Boa parvalbumin, however, while belonging to the p lineage, clusters within the fish in all reasonably parsimonious trees. The most parsimonious trees show many parallel or back mutations in the evolution of many parvalbumin residues, although the residues responsible for Ca*+ binding are very well conserved. These most parsimonious trees show an actinopterygian rather than a crossoptyrigian origin of the tetrapods in both the u and p groups. One of two electric eel parvalbumins is evolving more than 10 times faster than its paralogous partner, suggesting it may be on its way to becoming a pseudogene. It is concluded that varying rates of amino acid replacement, much homoplasy, considerable gene duplication, plus complicated lineages make the set of parvalbumin sequences unsuitable for systematic study of the origin of the tetrapods and other higher-taxa divergence, although it may be suitable within a genus or family.

Oncomodulin: The Enigmatic Parvalbumin Protein

“…First, recent phylogenetic analyses of parvalbumins have only been conducted using fish parvalbumins (Lee et al, 2007; Perez-Gordo et al, 2011). Second, phylogenetic analyses that include parvalbumin sequences outside of fish were performed mostly in the 1970s and 1980s, and thus used a limited number of parvalbumin sequences (Pechere et al, 1973; Goodman and Pechére, 1977; Cavé et al, 1982; Maeda et al, 1984; Moncrief et al, 1990). For example, the most recent phylogenetic analysis that included mammalian OCM used only 23 parvalbumin sequences, two of which were from mammals, and none from birds (Moncrief et al, 1990).…”