Query (optional)   in Class  All Allele Author Colleague Collection Assembly Gene Gene Class Gene Product Germplasm Image Journal Keyword Library Locus Map Map Data Marker Pathology Polymorphism Probe Protein QTL Rearrangement Reference Sequence Species Trait Trait Study Two Point Data  

---

GrainGenes Reference Report: PNA-92-9555

[Submit comment/correction]

Reference	PNA-92-9555
Title	Barley telomeres shorten during differentiation but grow in callus culture
Journal	Proceedings of the National Academy of Sciences, USA
Year	1995
Volume	92
Pages	9555-9559
Author	Kilian A Stiff C Kleinhofs A
Abstract	Eukaryotic chromosomes terminate with long stretches of short, guanine-rich repeats These repeats are added de novo by a specialized enzyme, telomerase In humans telomeres shorten during differentiation, presumably due to the absence of telomerase activity in somatic cells This phenomenon forms the basis for several models of telomere role in cellular senescence Barley (Hordeum vulgare L. telomeres consist of thousands of TTTAGGG repeats, closely resembling other higher eukaryotes. In vivo differentiation and aging resulted in reduction of terminal restriction fragment length paralleled by a decrease of telomere repeat number. Dedifferentiation in callus culture resulted in an increase of the terminal restriction fragment length and in the number of telomere repeats. Long-term callus cultures had very long telomeres. Absolute telomere lengths were genotype dependent, but the relative changes due to differentiation, dedifferentiation, and long-term callus culture were consistent among genotypes. A model is presented to describe the potential role of the telomere length in regulation of a cell's mitotic activity and senescence.
Keyword	callus [ Show all 12 ]

GrainGenes is a product of the Agricultural Research Service of the US Department of Agriculture.