212 Ebola messages in my mailbox...

[Francisco Muril Zerbini]

Thanks for the excellent and highly informative post. I'm looking forwrad 
to reading your paper with the multiple sequence aligments !

I have a few comments on your post:

On 16 May 1995, Ulrich Melcher wrote:

> The hypothesis that filoviruses have natural reservoirs in plants seems 
> far-fetched.
>(...) 
> Yet, stranger things have happened.  I therefore examined the 
> far-fetched possibility further.  The sequence searching that I have 
> done (detailed below for those interested) suggests that a natural 
> reservoir for Ebola in plants is highly unlikely.

That's the attitude that I like to see. I agree that the possibility is 
far-fetched, but also think that it should be investigated. You did just 
that and showed that it *is* indeed highly unlikely. 

> Thus, there is no likely relation between any Ebola protein and a known 
> movement protein, or with an unknown but sequenced movement protein.  
> The possibility remains that movement proteins of as yet unsequenced 
> plant viral groups may be related.  There are also some viruses (for 
> example, luteoviruses) that because of their limitation to phloem do not 
> require any movement protein function.

Good point about the luteos. There's a lot that we don't know about plant
virus movement. Also, it has been shown that some plant viruses use more
than one movement protein (eg, the bipartite geminiviruses use BR1 to get
out of the nucleus, and then BL1 to modify plasmodesmata and move
cell-to-cell). Did you include BR1 in your comparisons ? BTW, this has 
nothing to do with Ebola, but did you compare the movement proteins with 
plant proteins ? I'm wondering if you found any similarities that might 
suggest that plant virus movement proteins were originally plant 
proteins. 

I have been discussing the possibility of an insect host for Ebola (which
I think is more possible than a plant host) with an insect virologist, and
he thinks this is also highly unlikely (but for different reasons - no 
sequence comparisons here, just the fact that according to him it would 
have to be a blood-sucking insect and most of these have already been 
studied). 

Again, I think that the question of Ebola's natural host is a fundamental 
one. I'm sure that most of the paranoia and speculation will cease if the 
natural host is determined (just like happened with the Arenaviruses). 
It's about time !!

Murilo
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| Murilo Zerbini                   | Out of 3,000,000,000 DNA nucleotides, |
| Dep. of Plant Pathology          | human beings and chimpanzees have     |
| University of California, Davis  | 2,999,400,000 in common.              |
| fmzerbini at ucdavis.edu            |                                       | 
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