Open AccessMeiosis in Coprinus: characterization and activities of two forms of DNA polymerase during meiotic stages.
Author(s) -
Kengo Sakaguchi,
Benjamin C. Lu
Publication year - 1982
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.2.7.752
Subject(s) - dna polymerase , biology , polymerase , microbiology and biotechnology , dna clamp , dna polymerase ii , primer (cosmetics) , dna polymerase delta , dna polymerase i , dna polymerase mu , dna , biochemistry , coprinus , polymerase chain reaction , gene , chemistry , circular bacterial chromosome , reverse transcriptase , botany , organic chemistry
Two forms of DNA polymerase have been studied in the basidiomycete Coprinus. DNA polymerase from basidiocarp tissues at zygotene-pachytene stage has been purified 3,500-fold and defined as DNA polymerase b by virtue of its insensitivity to N-ethylmaleimide and by its low molecular weight (76,000). This enzyme has optimal activity at pH 7.0 to 7.5, at 200 mM KCl, and at 25 degrees C incubation temperature. It can use polycytidylic acid-oligo(dG)12-18 as template primer in addition to homodeoxypolymers. The DNA polymerase a is mainly produced in the exponentially growing mycelium. It is sensitive to N-ethylmaleimide and has a temperature optimum at 35 degrees C. At the premeiotic S phase, activities from both polymerase a and polymerase b are found in cell-free extracts. The b enzyme is the only DNA polymerase produced during meiotic prophase. Its assayable activity exhibits two peaks, one at premeiotic S stage and one at pachytene. It is possible that DNA polymerase b is responsible for pachytene repairs involved in recombination.