Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2001-7-25
pubmed:abstractText
Few biochemical and molecular details are available on microspore growth and development. In this work, a nuclease was partially purified from diffusates of barley (Hordeum vulgare L.) microspores by using concanavalin-A as ligand. The chromatographic preparation contained a 34-kDa protein with nucleolytic activity; the enzyme (called BMN: barley microspore nuclease) was very stable at pH > 8.0 and temperatures below 50 degrees C. Activity was highest at pH 5.6 and increased almost exponentially with temperature until a breakpoint between activity and stability was reached at 70 degrees C. Although BMN was able to cleave RNA, the enzyme showed a remarkable preference for DNA, especially in the single-stranded form. The best homopolymeric substrates were poly(dA) and poly(A), whereas poly(dC), poly(G) and poly(I) were almost completely uncleaved. When incubated with intact nuclei, BMN caused a nucleosomal DNA ladder of approximately 200 bp. On the basis of DNA laddering, substrate specificity, Mg2+ -dependence and best performance at apoplastic pH, BMN can be referred to as a putative apoptotic nuclease involved in pollen development.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0032-0935
pubmed:author
pubmed:issnType
Print
pubmed:volume
213
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
199-206
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Isolation and characterization of an endonuclease synthesized by barley (Hordeum vulgare L.) uninucleate microspores.
pubmed:affiliation
Dipartimento di Produzione Vegetale e Tecnologie Agrarie, University of Udine, Italy. stefano.marchetti@dpvta.uniud.it
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't