Transcription of the 'non-transcribed' spacer of Drosophila melanogaster rDNA
نویسندگان
چکیده
We have detected a set of transcripts in Drosophila melanogaster cells which are homologous to repeating elements within the 'non-transcribed' spacer region of rDNA. The RNA molecules range from 240 to 1680 nucleotides, differing in length by an integral value of 240 nucleotides. We have sequenced several AluI fragments which characterise the main 240 nucleotide repeating element. We find that each of these fragments contain a segment of approximately 50 nucleotides, which is homologous to the transcription initiation site for pre-rRNA.
منابع مشابه
Transient expression of Drosophila melanogaster rDNA promoter into cultured Drosophila cells.
Recombinant plasmids that carry the bacterial CAT gene under the transcriptional control of the D. melanogaster rDNA promoter have been introduced by transfection into cultured Schneider II Drosophila cells and their template activity followed at the RNA and protein level. While no CAT enzyme activity is measurable 48 hrs after transfection, high levels of hybrid rRNA-CAT transcripts that origi...
متن کاملNucleolar dominance of the Y chromosome in Drosophila melanogaster.
The rDNA genes are transcribed by RNA polymerase I to make structural RNAs for ribosomes. Hundreds of rDNA genes are typically arranged in an array that spans megabase pairs of DNA. These arrays are the major sites of transcription in growing cells, accounting for as much as 50% of RNA synthesis. The repetitive rDNA arrays are thought to use heterochromatic gene silencing as a mechanism for met...
متن کاملMultigene family of ribosomal DNA in Drosophila melanogaster reveals contrasting patterns of homogenization for IGS and ITS spacer regions. A possible mechanism to resolve this paradox.
The multigene family of rDNA in Drosophila reveals high levels of within-species homogeneity and between-species diversity. This pattern of mutation distribution is known as concerted evolution and is considered to be due to a variety of genomic mechanisms of turnover (e.g., unequal crossing over and gene conversion) that underpin the process of molecular drive. The dynamics of spread of mutant...
متن کاملToxicological Evaluation of a New Lepidopteran Insecticide, Flubendiamide, in Non-Target Drosophila melanogaster Meigen (Diptera: Drosophilidae)
Background: Flubendiamide, comparatively a new pesticide designed to eradicate lepidopteran insect pests is known to have low risk to birds, mammals, fish, algae, honey bees, non-target arthropods, earthworms, soil macro- and micro-organisms, non-target plants as well as sewage treatment organisms; however, the risk assessment for aquatic invertebrates from metabolite could not be finalized wit...
متن کاملMultiple repeated units in Drosophila melanogaster ribosomal DNA spacer stimulate rRNA precursor transcription.
Drosophila melanogaster ribosomal DNA (rDNA) transcriptional units are separated by nontranscribed spacer (NTS) segments consisting of tandemly arranged repeats 95, 330, and 240 base pairs long. NTS sequences stimulate transcription from the rRNA precursor (pre-rRNA) promoter. Primer extension analysis of RNA from cells cotransfected with plasmids carrying NTS sequences of various lengths shows...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Nucleic acids research
دوره 11 1 شماره
صفحات -
تاریخ انتشار 1983