tobacco rRNA sizes ?

[Leonard N. Bloksberg]

In Article <1993Oct26.093336.583 at gserv1.dl.ac.uk> "suter at de.d400.mpg.MPIZ-KOELN.VAX" says:
> dear humans,
> 
> on a northern i see with my probe two signals, of 1200 and 4800 nucleotides.
> as always, i am a little scared this could be the result of cross-hybridization
> with a very abundant RNA, like ribosomal. 
> 
> What are the sizes of ribosomal RNAs in tobacco ???????
> 
> tia, clemens
> ===============================================================================
> Dr. Clemens Suter-Crazzolara, PhD
> Max-Planck-Institut fuer Zuechtungsforschung
> Abteilung Genetische Grundlagen der Zuechtungsforschung
> Carl-von-Linne Weg 10,        D-50829 Koeln, Germany
> Tel.xx49.221.5062-221    Fax.-213      e-mail: suter at vax.mpiz-koeln.mpg.d400.de
> ===============================================================================
> 
Well, since RNA tends to run oddly, and I don't know wether your standards 
are ssDNA, dsDNA, or RNA, I can't rightly say.  But, you could answer the 
question yourself (and more accurately than I ever could) by looking at
your Ethidium bromide stained RNA gel.  Where do the rRNA bands run?  Do 
they line up exactly with your mistery bands?  If this is a problem, you 
could try several things:
.
.	1.	Use poly-A RNA instead of total.
.	2.	Make sure your mRNA is still in tact (pos. cntrl probe).
.			If not, make better quality RNA.
.	3.	Find a homologous (not heterologous) probe.
.
Good Luck.
.
.			Leonard N. Bloksberg
.			Bloksber at pilot.msu.edu
.
.