Chromatin diminution in Ascaris suum: nucleotide sequence of the eliminated satellite DNA.
نویسندگان
چکیده
We have determined the prototype sequence of the DNA which is eliminated in the course of chromatin diminution in Ascaris suum. This DNA which is virtually absent from somatic cells but retained in the germ line consists predominantly of highly repetitive sequences which are variants of an AT rich 123 base pair repeat unit. Both major and minor variants have been sequenced. The overall structure of this germ line limited DNA corresponds to the segmental organization characteristic of satellite DNAs. Possible correlations between the mechanism of chromatin diminution and some properties of the satellite sequence are discussed.
منابع مشابه
Silencing of germline-expressed genes by DNA elimination in somatic cells.
Chromatin diminution is the programmed elimination of specific DNA sequences during development. It occurs in diverse species, but the function(s) of diminution and the specificity of sequence loss remain largely unknown. Diminution in the nematode Ascaris suum occurs during early embryonic cleavages and leads to the loss of germline genome sequences and the formation of a distinct genome in so...
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عنوان ژورنال:
- Nucleic acids research
دوره 10 11 شماره
صفحات -
تاریخ انتشار 1982