kDNA minicircles - forwarded

[Dmitri Maslov]

Relatively short ORFs are rather frequently found in minicircles. In
addition to the examples given by Dr. Barker a while ago we found eight ORFs
longer than 100 amino acids in a minicircle from Crithidia oncopelti (Pestov
et al (1990) MBP 41:135-146), with the longest ORF being 163 aa long.
However, since in no case one could see a corresponding transcript, the
significance of these ORFs is unclear.



At 08:42 AM 3/24/98 -0300, you wrote:
>>From: root at cscdri.ren.nic.in
>>>From: Superuser <root at cscdri.ren.nic.in>
>>To: j.taverne at ucl.ac.uk
>>Date: Tue, 24 Mar 98 8:51:15 PST
>>
>>        Since I cannot access the parasitology biotech forum
>>directly from my end, that's why I am writing to you to
>>kindly float my following query for an answer, to parasitology
>>colleagues.
>>        During the course of my DNA sequencing of kDNA minicircles
>>of an isolate of Leishmania, I have come across an open reading
>>frame. It is of 93 a.a. and codes for an extremely hydrophobic
>>putative protein of 10 kD. An ORF in the variable region of
>>minicircles is highly surprising to me as I thought that they do
>>not code for proteins. But by northern blot analysis I could even
>>detect a transcript! This then prompted me to express the ORF in
>>E. coli. I got the expression library with the insert in the right
>>orientation etc but I cannot see the protein on SDS-PAGE. Could
>>it be that the protein is not finally translated or is its extreme
>>hydrophobicity giving a problem? Looking forward eagerly to some
>>suggestions.
>>        Neeloo Singh (root at cscdri.ren.nic.in)
>>
>
>
>

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Dmitri A. Maslov
University of California - Riverside, Department of Biology
3401 Watkins Drive, Riverside, CA 92521, USA
Tel: 909-787-6485 (office), 909-787-5235 (lab)
E-mail: dmitri.maslov at ucr.edu or maslov at ucrac1.ucr.edu
http://cnas.ucr.edu/~bio/faculty/Maslov.html
Fax (departmental) 909-787-4286
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