Nakisah Mat Amin* and ¹Keith Vickerman

Unit of Biological Sciences, Faculty of Science and Professional Arts, Universiti Putra Malaysia Terengganu, Mengabang Telipot 21030 Kuala Terengganu, Malaysia, 1Division of Environmental Evolutionary Biology, Graham Kerr Building, University of Glasgow, G12 8QQ, Scotland, UK.

(Received 9 January 1998 / Accepted 23 February 1998)

Abstract.
A fluorescence technique has been employed to visualise nuclear division in Naegleria gruberi. The synchronously dividing Naegleria cells were stained with anti a-tubulin as a primay antibody and with a fluorescein isothiocyanate labelled goat anti mouse immunoglobin (FITC) as a secondary antibody. The cells were also stained with 4 1 6-diamidino-2-phenylindole DAP1) and propidium iodide (PI) to stain the nucleus. The results of this study indicated that by using anti (a tubulin, cytoplasmic microtubules; and mitotic spindles of Naegleria gruberi can be visualised under fluorescence microscopy. By this technique, a centrosome with associated microtubules was found to be present in the cytoplasm of Naegleria during nuclear division and this finding contradicts the previous idea that this organelle does not exist in Naegleria. The centrosome appeared to divide during prophase but it could not be detected later at metaphase telophase.

Keywords: Anti a tubulin, 4', 6 diamidino 2 phenylindole DAP1) Propidium Iodide (PI), Centrosome, Spindle Microtubules

*Author for Correspondence.
J Mumford,
Centre for Environmental Policy,
Imperial College London,
Silwood Park, Ascot, Berkshire,
SL5 7PY, UK.
Email: This email address is being protected from spambots. You need JavaScript enabled to view it..

Abstract.
This short note gives an update on the deployment of innovative genetic vector control strategies since the publication of the original paper in 2009. Rapid progress is being made in field activities with genetically modified Aedes aegypti that express a self-limiting trait. The process by which countries make decisions on risk assessment and management for these GM mosquitoes within their national frameworks is developing. National approvals are essential prerequisites to such field releases. This note also briefly updates on the activities of other initiatives described in the original paper, including the MosqGuide project. Original papers were published in Asia Pacific Journal of Molecular Biology and Biotechnology (2009) 17(3) 75-85 and 93-95.

1. Ismail* and S.M. Smith

Institute of Cell and Molecular Biology, University of Edinburgh, the King's Buildings, Mayfield Road, Edinburgh, EH9 3JH, United Kingdom

Received 16 June 2000 / Accepted 28 July 2000

Abstract.
Regulation of malate synthase (MS) and isocitrate lyase (ICL) gene at the posttranscriptional level was studied using actinomycin D, a transcription inhibitor. Detached roots which contained an abundance of NIS and ICL transcripts due to starvation for 4 days, showed a decrease in mRNA amount of about 50% after 3 h incubation in the presence of 10 ug/mI actinomycin D. In contrast, when sucrose was added together with actinomycin D, MS and ICL mRNA decreased to a much lower level within 3 h. Therefore, NIS and ICL half lives appear much shorter in the presence of sugar. Similar results were obtained with detached cotyledons. Confirmation that actinomycin D had effectively stopped transcription was obtained by showing that it prevented light induced expression of hydroxypyruvate reductase and rubisco genes in cotyledons. Thus, NIS and ICL genes appear to be regulated by sugars at the levels of transcription and mRNA stability.

Keywords: Actinomycin D, cucumber (Cucumis sativus), gene expression, glyoxylate cycle, mRNA stability