Glu-D1bn{03124}. 5*t+12{03124}.
dv: Ae. tauschii.
Glu-D1 {421} appears to have
arison as the result of a deficiency of subunit 12 from Glu-D1a
(2+12); subunits 2 and 12 are referred to as D1 and D5 in {421}. One of the
Glu-D1o subunits has been numbered 13 in {755}; 13 was previously
used to number a subunit encoded by Glu-B1f {13+16} and
Glu-B1g {13+19} {1116}. Subunit 9 of Glu-D1g (5+9) was so
numbered in {478} because its mobility is the same as one of the subunits
encoded by Glu-B1c (7+9). Five combinations involving 6 HMW subunits
[1D {p-t}] are listed in {420}. Eleven additional Glu-D1 alleles in
T. tauschii were described {755}. Seven transfers of Glu-D1a
and 10 of Glu-D1d (5+10) from chromosome 1D to chromosome 1A in
triticale were described {846}. The subunit 2.2* encoded by Glu-D1al
above and Glu-D1-1m in the appropriate list below has an unusually
high Mr comparison of its N-terminal sequence and amino acid composition
with those of subunit 2 (encoded by Glu-D1-1a indicated that its
greater Mr, could be due to the presence of a larger central repetitive
domain, although further evidence suggested that this does not affect the
conformational properties of the subunit {02107}. The alleles originally
designated Glu-D1w (encoding 'subunits' 2 (or 2t denoting
its origin in the Ae. tauschii genome) +T1+T2), Glu-D1af
(encoding 3 9or 3t)+T1+T2) and Glu-D1ag (encoding 1.5
(or1.5t)+T1+T2) share the component T1 that was originally
classified as a HMW glutenin. However, it has since been shown {02108} that
this protein is soluble in aqueous ethanol, casting doubt upon this
classification. More recently, it has been shown {02109}, from one and two
dimensional gel electrophoresis based upon SDS-PAGE and A-PAGE, and from
N-terminal sequencing, that this protein is an omega-gliadin of unusually
low electrophoretic mobility in SDS-PAGE, encoded by a locus located on the
short arm of chromosome 1D, though distant 913.18cM) from the principle
gliadin-encoding locus on 1D, Gli-D1, and 40.20cM from the high
molecular weight encoding locus, Glu-D1. The authors named the locus
Gli-DT1 (see below, section Gliadins). Reference to T1 was
consequently removed from the Glu-D1 list. As a consequence of this
finding, allele Glu-D1w was reused for a distinct allele, and
Glu-D1af was omitted and will be reused for a future allele, since
the combinations of subunits that these alleles originally represented are
no longer unique. In {03124}, null alleles were observed for both
Glu-D1-1 and Glu-D1-2,which, naturally, are not necessarily
the same as those previously reported for this locus, meaning that composite
alleles involving them in this study and corresponding to combinations
apparently already listed in the Catalogue, may, in fact, represent novel
alleles. It is also found that certain subunits of apparently identical
relative mobility in SDS-PAGE showed different surface hydrophobocities in
RP-HPLC; and the reverse situation was also observed (the same
hydrophobicity, but different electrophoretic mobilities). It was shown
{03126} that the relatively small size of a y-type HMW glutenin subunit,
named 12.4t (encoded by Glu-D1-1t {03124} - see the
relevant list below) and carried by accession CPI110750 of Ae.
tauschii, is due to the deletion of blocks of repetitive motifs,
amounting to approximately 200 amino acids, probably caused by unequal
crossing-over. Note that the cultivar Fiorello is given as a standard for
Glu-D1h encoding subunits 5+12 and for Glu-D1w encoding
subunits 5*+10. An attempt to resolve this apparent conflict will be made in
a future update. Alleles and subunits at Glu-A1-1 and
Glu-A1-2: Glu-A1-1 encodes X-type glutenins and
Glu-A1-2 encodes y-type glutenins.