Protoplasma

, Volume 150, Issue 2, pp 150–159

Specialization of the inner cortex for ureide production in soybean root nodules

  • E. H. Newcomb
  • Y. Kaneko
  • K. A. VandenBosch
Article

DOI: 10.1007/BF01403671

Cite this article as:
Newcomb, E.H., Kaneko, Y. & VandenBosch, K.A. Protoplasma (1989) 150: 150. doi:10.1007/BF01403671

Summary

The possibility that cells in the inner cortex of determinate root nodules participate in ureide production from recently fixed N2, as do the uninfected (interstitial) cells of the infected central region, has been investigated in soybean (Glycine max) inoculated as seeds withBradyrhizobium japonicum. Like the interstitial cells, cells of the three innermost cortical layers produce enlarged peroxisomes and a meshwork of tubular ER during differentiation. These changes are most pronounced in the innermost cortical layer, are successively less so in the 2nd and 3rd layers, and are usually undetectable in more distant layers. Peroxisomes in the inner three layers are stained in the DAB (3,3′-diaminobenzidine) test for uricase (EC 1.7.3.3) activity, indicative of the potential for ureide formation, but peroxisomes in more distant cortical cells are not stained. A nodulespecific uricase also is demonstrable in the inner three cortical layers by immunogold labeling enhanced with silver for visualization in the light microscope. The observations suggest that with respect to ureide production the cells of the inner layers of the cortex are functionally similar to the interstitial cells of the infected region despite the apparent distinctiveness of the two regions anatomically.

Keywords

Inner cortexPeroxisomesRoot-nodulesSoybeanUricase cytochemistry

Abbreviations

DAB

3,3′-diaminobenzidine

ER

endoplasmic reticulum

Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • E. H. Newcomb
    • 1
  • Y. Kaneko
    • 2
  • K. A. VandenBosch
    • 3
  1. 1.Department of BotanyUniversity of Wisconsin-MadisonMadison
  2. 2.Department of Regulation BiologySaitama UniversityUrawa
  3. 3.Department of BiologyTexas ASM UniversityCollege Station