Evolutionary Studies on Teleost Hemoglobin Sequences
357
investigations [2]. However, now we arranged in tandem not only
globin chains which occur in the same hemoglobin components, like
trout (Oncorhynchus mykiss) HbI and HbIV, and which may be derived
from adjacent a- and J3-globin genes on the same chromosome, but also
"minor" notothenioid hemoglobin chains like those of Pleuragramma
antarcticum (Hb3 and Hb2) and Trematomus newnesi (Hb2 and HbC),
which are at congruent positions in the separate a- and J3-trees, but
which do not occur in one hemoglobin component. On the contrary, in
P. antarcticum three major hemoglobin components occur: Hb I
consisting of the two "major" chains, Hb2 with the "major" a- and the
"minor" 13-, and Hb3 with the "minor" a- and the "major" J3-chain [6].
Three tandemly arranged MPT trees were obtained, each requiring
1293 substitutions. They differ in details of the topology near trout HbI
and electric eel Hb. One of the three trees is shown in Fig. 1. Bootstrap
values using a 50% majority rule are also indicated.
Strong support (100% bootstrap values) is again obtained for the
monophyly of teleost hemoglobins, of the cluster of "major" and
"minor" Notothenioid, T. thynnus and C. kumu hemoglobins and of the
"major" Notothenioid hemoglobin chains (except Pseudaphritis
urvillii).
Notothenia coriiceps Hemoglobin PI and P2
Two sets of adjacent a- and J3-hemoglobin genes have been sequenced
from DNA of N coriiceps. The deduced amino acid sequences differ
from those expressed in the adult and may be juvenile sequences. The
a-chains are identical, while the J3-chains differ at only four positions,
which may indicate that the two sets originate from a recent gene
duplication. These deduced sequences group in the tree (Fig. 1) with the
"minor" notothenioid chains. However, they diverge from them before
species divergences in the notothenioids, but - in the J3-tree - after
divergence of sequences of P. urvillii and C. gobio (not shown).
Cottoperca gobio Hemoglobin I
The incomplete sequences of C. gobio hemoglobin occupy in the trees
different positions. In the a-trees C. gobio groups with the "major"
Notothenioid chains: in one of the two most parsimonious trees as the
first diverging taxon, in the other one monophyletic with P. urvillii (not
shown). In the most parsimonious J3-trees C. gobio groups with the
"minor" Notothenioid chains (diverging before P. urvillii, not shown).
357
investigations [2]. However, now we arranged in tandem not only
globin chains which occur in the same hemoglobin components, like
trout (Oncorhynchus mykiss) HbI and HbIV, and which may be derived
from adjacent a- and J3-globin genes on the same chromosome, but also
"minor" notothenioid hemoglobin chains like those of Pleuragramma
antarcticum (Hb3 and Hb2) and Trematomus newnesi (Hb2 and HbC),
which are at congruent positions in the separate a- and J3-trees, but
which do not occur in one hemoglobin component. On the contrary, in
P. antarcticum three major hemoglobin components occur: Hb I
consisting of the two "major" chains, Hb2 with the "major" a- and the
"minor" 13-, and Hb3 with the "minor" a- and the "major" J3-chain [6].
Three tandemly arranged MPT trees were obtained, each requiring
1293 substitutions. They differ in details of the topology near trout HbI
and electric eel Hb. One of the three trees is shown in Fig. 1. Bootstrap
values using a 50% majority rule are also indicated.
Strong support (100% bootstrap values) is again obtained for the
monophyly of teleost hemoglobins, of the cluster of "major" and
"minor" Notothenioid, T. thynnus and C. kumu hemoglobins and of the
"major" Notothenioid hemoglobin chains (except Pseudaphritis
urvillii).
Notothenia coriiceps Hemoglobin PI and P2
Two sets of adjacent a- and J3-hemoglobin genes have been sequenced
from DNA of N coriiceps. The deduced amino acid sequences differ
from those expressed in the adult and may be juvenile sequences. The
a-chains are identical, while the J3-chains differ at only four positions,
which may indicate that the two sets originate from a recent gene
duplication. These deduced sequences group in the tree (Fig. 1) with the
"minor" notothenioid chains. However, they diverge from them before
species divergences in the notothenioids, but - in the J3-tree - after
divergence of sequences of P. urvillii and C. gobio (not shown).
Cottoperca gobio Hemoglobin I
The incomplete sequences of C. gobio hemoglobin occupy in the trees
different positions. In the a-trees C. gobio groups with the "major"
Notothenioid chains: in one of the two most parsimonious trees as the
first diverging taxon, in the other one monophyletic with P. urvillii (not
shown). In the most parsimonious J3-trees C. gobio groups with the
"minor" Notothenioid chains (diverging before P. urvillii, not shown).