Linked Life Data

15517348

Source:http://linkedlifedata.com/resource/pubmed/id/15517348

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2005-4-21
pubmed:abstractText
Tobacco (Nicotiana tabacum L.) microspores at the time of mitosis are characterized by the abundant occurrence of 92- and 98-kDa glycoproteins (GP92 and GP98). GP92 is a soluble protein while GP98 is bound to the insoluble microspore fraction. Both glycoproteins were isolated by affinity chromatography and SDS-PAGE and analysed by MS. Peptide sequences were determined by mu-HPLC/nano-ESI-MS/MS (electrospray ionization tandem MS). GP92 displayed homology to beta-galactosidase (EC 3.2.1.23) and GP98 to beta-xylosidase (EC 3.2.1.37) from Arabidopsis thaliana (L.) Heynh. The activities of the two enzymes in microspore and pollen extracts of tobacco exhibited similar developmental changes to the occurrence of GP92 and GP98, with a maximum around microspore mitosis. These two glycoproteins are the first identified enzymes characteristic of mitotic microspores. Arabidopsis transcriptomic data for five beta-galactosidase and three beta-xylosidase genes abundantly expressed in pollen were verified by reverse transcription-PCR of RNA from different stages of Arabidopsis pollen development and from various parts of the sporophyte. The results showed abundant expression of two genes (At5g20710, At1g31740) homologous to tobacco GP92 in microspores and early pollen, and of three genes (At5g56870, At2g16730 and At4g35010) in maturing pollen. Analysis of beta-xylosidases showed abundant expression of a late pollen-specific gene At3g62710 and low expression of an early gene At5g10560. It is suggested that the early beta-galactosidase and beta-xylosidase genes may participate in cell wall loosening associated with pollen expansion after microspore mitosis and that the products of the late genes may play a role in cell expansion during pollen germination.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0032-0935
pubmed:author
pubmed:issnType
Print
pubmed:volume
220
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
931-40
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Expression of beta-galactosidase and beta-xylosidase genes during microspore and pollen development.
pubmed:affiliation
Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Na Perníkárce 15, 160 00, Prague 6, Czech Republic. hruba@ueb.cas.cz
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't