SciELO - Scientific Electronic Library Online

 
vol.42 issue4Bioactivity of crude ethanol extract and fractions of Eugenia uniflora (Myrtaceae) in the hepatopancreas of Oreochromis niloticus L author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

  • On index processCited by Google
  • Have no similar articlesSimilars in SciELO
  • On index processSimilars in Google

Share


Biological Research

Print version ISSN 0716-9760

Abstract

LIU, ZHAO; YI-SONG, LI; JUN-GANG, LI  and  FU-KANG, GU. Some ultrastructural observations of the vegetative, resting and excysting ciliate, urostyla grandis (urostylidae, hypotrichida). Biol. Res. [online]. 2009, vol.42, n.4, pp.395-401. ISSN 0716-9760.  http://dx.doi.org/10.4067/S0716-97602009000400001.

In order to reveal the differentiation characteristics of organelles of ciliates under different physiological status, the cellular ultrastructure of Urostyla grandis was studied by transmission electron microscopy. In the resting cells most ciliary shafts, kinetosomes and sub-pellicle microtubules were resorbed, and the endoplasmic reticulum (ER) disappeared with the autophagocytosis taking place within the cytoplasm. As well, the nuclear matrix of the macronucleus was extruded into the cytoplasm, forming pseudopodia-like structures with large quantities of heterochromatin (CH) attached to the inner nuclear membrane. During excystment, membraneous structures developed and gradually increased in number to form the ER. Autophagic vacuoles (AVs) appeared containing mitochondria, paraglycogen particles (PGP), membranous structures, etc. Moreover, the number of nucleoli decreased with the chromatin, condensing in parallel with the process of recombination. Based on these observations, it could be concluded that the de-differentiation of microtubular organelles and the changes occurring in macronuclei in the resting Urostyla grandis, as well as the differentiation of cytoplasmic organelles, digestion by AVs, and the recombination of chromatin during excystment, are not similar to events that occur in non-kinetosome-resorbing cysts (NKR).

Keywords : Urostyla grandis; Ultrastructure; Vegetative cell; Resting cell; Excysting cell.

        · text in English     · English ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License