Cytogenetic and molecular characterization of the Abies alb a genome and its relationship with other members of the Pinaceae
Abstract Genome size, karyotype structure, heterochromatin distribution, position and number of ribosomal genes, as well as the ITS2 sequence of the internal transcribed spacer (ITS) were analysed in silver fir ( Abies alba Mill.). The analysis also included characterization of the Arabidopsis ‐type...
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Published in | Plant biology (Stuttgart, Germany) Vol. 10; no. 2; pp. 256 - 267 |
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Main Authors | , , , , , , |
Format | Journal Article |
Language | English |
Published |
01.03.2008
|
Online Access | Get full text |
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Summary: | Abstract
Genome size, karyotype structure, heterochromatin distribution, position and number of ribosomal genes, as well as the ITS2 sequence of the internal transcribed spacer (ITS) were analysed in silver fir (
Abies alba
Mill.). The analysis also included characterization of the
Arabidopsis
‐type of telomeric repeats in silver fir and in related species. The results were compared with results from other species of the Pinaceae, to evaluate phylogeny and chromosomal and molecular evolution in the Pinaceae. Integrated chromosomal data provided insights into chromosome and karyotype evolution in the Pinaceae. The evolutionary trend for GC‐rich heterochromatic blocks seems to involve loss of blocks that are not associated with rDNA. Similarly, numerous large blocks of interstitial plant telomeric repeats that are typical for all analysed species of the genus
Pinus
were not observed in the evolutionarily younger genera, such as
Abies, Picea
and
Larix.
On the contrary, the majority of telomeric sequences in these three genera appeared confined to the chromosome ends. We confirmed the current position of
Abies
and
Tsuga
in subfamily Abietoideae and the position of
Pinus
in the subfamily Pinoideae based on ITS2 sequences.
Pseudotsuga
is placed together with
Larix
into the subfamily Laricoideae. We conclude that the current position of the genus
Picea
in the subfamily Abietoideae should be reconsidered and, possibly, the genus
Picea
should be reclassified as a separate subfamily, Piceoideae, as recently proposed. |
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ISSN: | 1435-8603 1438-8677 |
DOI: | 10.1111/j.1438-8677.2007.00018.x |