ISSN:
1432-1432
Keywords:
Balbiani rings
;
Evolution
;
Immunological detection
;
Nucleotide sequence
;
3′ End
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Two cDNA clones representing the 3′-end regions of BR1 and BR2 75S mRNA were obtained fromChironomus pallidivittatus. The regular structure characterizing the core of these genes, consisting of tandemly arranged repeat units, changes into a more irregular structure toward the 3′ end. Distal to a standard type of repeat unit with a characteristic excess of positive charges, a new type of repeat with a high, negative charge density is interspersed among parts of the standard unit. The last 111 amino acids before the stop codon represent a unique region distinctly different in amino acid composition from upstream regions, and include two partially homologous hydrophobic regions. Sequence comparison of 3′-end regions from clones representing BR1 and BR2 genes indicates striking sequence conservation in the unique part of the region. Analysis of the level of silent site divergence shows that the homology increases in the 3′ direction up to the polyadenylation site. That the unique region is retained as a part of the secreted protein is shown by Western blotting.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02100037
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