Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Characterization of an HSP70 Cognate Gene Family in Arabidopsis

Cathy H. Wu, Timothy Caspar, John Browse, Susan Lindquist and Chris Somerville
Plant Physiology
Vol. 88, No. 3 (Nov., 1988), pp. 731-740
Stable URL: http://www.jstor.org/stable/4271647
Page Count: 10
  • Read Online (Free)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Characterization of an HSP70 Cognate Gene Family in Arabidopsis
Preview not available

Abstract

Analysis of the polypeptide composition of extracts from heat-shocked leaves of Arabidopsis indicated the presence of at least 12 HSP70-related polypeptides, most of which were constitutively expressed. In vitro translation of mRNA from heat-shocked and control leaves indicated that the amount of mRNA encoding four HSP70 polypeptides was increased strongly by heat-shock. Three Arabidopsis genes which exhibit homology to a Drosophila HSP70 gene were cloned. Two of the three genes are arranged in direct orientation approximately 1.5 kilobases apart. The third gene is not closely linked to the other two. Nucleotide sequence analysis of the 5′ regions of the two linked genes revealed that both contain a TATA box, the CAAT motif, and several short sequences which are homologous to the Drosophila heat-shock consensus sequence. The deduced partial amino acid sequence of the open reading frames were 79 and 72% homologous to the corresponding regions of the Drosophila HSP70-cognate and HSP70 sequences, respectively. As with the two maize HSP70 genes which have been characterized, and the Drosophila HSP70-cognate genes, the Arabidopsis genes contained a putative intron in the codon specifying amino acid 72. Analysis of mRNA levels with gene-specific oligonucleotide probes indicated that two of the genes were not expressed or were expressed at very low levels in leaves during normal growth or after heat-shock, whereas the other gene was constitutively expressed. By analogy with the results of similar studies of other organisms, it appears that the three cloned genes are members of a small family which are most closely related to the HSP70-cognate genes found in other species.

Page Thumbnails

  • Thumbnail: Page 
731
    731
  • Thumbnail: Page 
732
    732
  • Thumbnail: Page 
733
    733
  • Thumbnail: Page 
734
    734
  • Thumbnail: Page 
735
    735
  • Thumbnail: Page 
736
    736
  • Thumbnail: Page 
737
    737
  • Thumbnail: Page 
738
    738
  • Thumbnail: Page 
739
    739
  • Thumbnail: Page 
740
    740