TY - JOUR
T1 - Pericentromeric regions of soybean (Glycine max L. Merr.) chromosomes consist of retroelements and tandemly repeated DNA and are structurally and evolutionarily labile
AU - Lin, Jer Young
AU - Jacobus, Barbara Hass
AU - SanMiguel, Phillip
AU - Walling, Jason G.
AU - Yuan, Yinan
AU - Shoemaker, Randy C.
AU - Young, Nevin D.
AU - Jackson, Scott A.
PY - 2005/7
Y1 - 2005/7
N2 - Little is known about the physical makeup of heterochromatin in the soybean (Glycine max L. Merr.) genome. Using DNA sequencing and molecular cytogenetics, an initial analysis of the repetitive fraction of the soybean genome is presented. BAC 076J21, derived from linkage group L, has sequences conserved in the pericentromeric heterochromatin of all 20 chromosomes. FISH analysis of this BAC and three subclones on pachytene chromosomes revealed relatively strict partitioning of the heterochromatic and euchromatic regions. Sequence analysis showed that this BAC consists primarily of repetitive sequences such as a 102-bp tandem repeat with sequence identity to a previously characterized ∼120-bp repeat (STR120). Fragments of Calypso-like retroelements, a recently inserted SIRE1 element, and a SIRE1 solo LTR were present within this BAC. Some of these sequences are methylated and are not conserved outside of G. max and G. soja, a close relative of soybean, except for STR102, which hybridized to a restriction fragment from G. latifolia. These data present a picture of the repetitive fraction of the soybean genome that is highly concentrated in the pericentromeric regions, consisting of rapidly evolving tandem repeats with interspersed retroelements.
AB - Little is known about the physical makeup of heterochromatin in the soybean (Glycine max L. Merr.) genome. Using DNA sequencing and molecular cytogenetics, an initial analysis of the repetitive fraction of the soybean genome is presented. BAC 076J21, derived from linkage group L, has sequences conserved in the pericentromeric heterochromatin of all 20 chromosomes. FISH analysis of this BAC and three subclones on pachytene chromosomes revealed relatively strict partitioning of the heterochromatic and euchromatic regions. Sequence analysis showed that this BAC consists primarily of repetitive sequences such as a 102-bp tandem repeat with sequence identity to a previously characterized ∼120-bp repeat (STR120). Fragments of Calypso-like retroelements, a recently inserted SIRE1 element, and a SIRE1 solo LTR were present within this BAC. Some of these sequences are methylated and are not conserved outside of G. max and G. soja, a close relative of soybean, except for STR102, which hybridized to a restriction fragment from G. latifolia. These data present a picture of the repetitive fraction of the soybean genome that is highly concentrated in the pericentromeric regions, consisting of rapidly evolving tandem repeats with interspersed retroelements.
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U2 - 10.1534/genetics.105.041616
DO - 10.1534/genetics.105.041616
M3 - Article
C2 - 15879505
AN - SCOPUS:23344438076
SN - 0016-6731
VL - 170
SP - 1221
EP - 1230
JO - Genetics
JF - Genetics
IS - 3
ER -