These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The role of the direct repeat in qut-controlled antitermination in phage lambda.
    Author: Kur J, Hradecna Z, Hasan N, Szybalski W.
    Journal: Virology; 1990 Jun; 176(2):629-32. PubMed ID: 2140632.
    Abstract:
    For antitermination of transcription from the late p'R promoter of phage lambda, a cis-acting qut sequence, which overlaps with p'R, is required, together with the product of lambda gene Q. Using our BspMI-mediated multicycle technique for generation of precise deletions, we have confirmed that deletions removing DNA downstream of +18 bp (counted from the p'R-controlled transcriptional start point s'R = +1) do not affect the efficiency of qut antitermination; at the same time we found that deleting one more bp (shifting the right-hand boundary to bp +17) reduces antitermination by only 20%. Deleting another 5 or 6 bp (+11 or +12 bp right-hand qut boundary), decreases antitermination by about 80%. These deletions reduce the 9/10-bp-direct repeat (5'-TGGGT(A or T)AATT)2 in qut to only the five italicized bp. Similar strong reduction in antitermination (by about 68%) was obtained with +16 bp qut boundaries, in constructs which also contained 2- or 3-bp insertions between bp +11 and +12 or between +12 and +13. Since the latter deletions retain only 5/10 bp of the direct repeat, it appears that antitermination is dependent on the length and intactness of the direct repeat.
    [Abstract] [Full Text] [Related] [New Search]