Distribution of nuclear pores and perinuclear dense substances in spermatocytes I of some oedionychina fleabeetles

  • Virkki N
  • Kimura M
  • 1


    Mendeley users who have this article in their library.
  • 8


    Citations of this article.


The nuclear envelope of growing postpachytene spermatocyte I differs notably in structure between the fleabeetles Omophoita cyanipennis and Oedionychus bicolor. The former species shows a more conventional structure with an even and probably random distribution of nuclear pores, and a strongly electron-opaque layer of fibrogranular material (FM) separated from the outer nuclear membrane by an intermediate layer of about 40 nm thickness. Peripherally from the FM layer, a continuous corona of granular dense material (GM) is accumulated around the nucleus. In Oedionychus, all nuclear pores are clustered in "nuclear sieves", i.e., shallow, cup-like indentations of the nuclear envelope. The sieves are filled with an electron-opaque substance resembling the FM of the Omophoita spermatocytes. This substance is kept at a distance of about 40 nm from the outer nuclear membrane. GM is produced only at the sieves, and is thus discontinuous. The sieves with their contents are called nuclear sieve complexes (NSC). © 1978.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Niilo Virkki

  • Michio Kimura

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free