Who is the guilty of this vegetable crime?

There is no other culpable than Cucumovirus, which can be identified if looking to it  you are able to diferenciate a non-enveloped, spherical virion of about 29 nanometers in diameter, which has a T=3 icosahedral symmetry composed of 180 coat proteins: 12 pentamers and 20 hexamers.

Image 2.1. Picture about the real 
morfology of CMV

How this murderer is formed of?

It is not an easy question, and there must have being other researchs before answering this issue. His structure is formed of a segmented tripartite linear RNA composed of RNA1, RNA2 and RNA3. Each genomic segment is 3' tRNA-like structure and a 5' cap.

Image 2.2. Position of dierent RNA that compose the 
segmented tripartite linear virus RNA

This Cucumovirus expresses himself by using the RNA as a messager RNAs. Then, RNA1 and RNA2 encode proteins 1a and 2a, involved in the genome replication and internal transcription of sgRNA4 from the negative copy of RNA3. HRNA3 is translated into a movement protein, while sgRNA4 it translates to a capsid one. Apart from this, ORF2b, present at RNA2, encodes a viral supressor of RNA silencing.

How does it commit the crimes?

When the expression is done, virus expresses the protein 1st and 2nd to produce replication proteins, as I have mentioned before, on the viral factory and after it transcribes/replicates providing new ssRNA genomic (new viruses).

Everithing continues translating RNA4 that produces the capsid that envolves the ssRNA genome, and assemblying this virus particles.

Image 2.3. Picture of diferent viral factories for viruses

Finally, it is the turn of the viral movement protein, that triggers the information of tubular structures that mediate viron cell-to-cell transfer via a tubule-guided mechanism.

How the murderer achieves to penetrate a really complex security system?

I am gonna explain the mechanism of commiting murder used by this relentless virus. 

Image 4.1. Insects being 
vectors of the virus

First of all, this murderer has to be transmitted from somewhere, and this Bromoviridae family virus, arrives to the host in two possible ways. The first, by a mechanical inoculation in plant by an insect, and the second is even simple, staying in contact one plant with another. 

Image 4.2. Vegetable cells that
shows easily the tonoplast

After have penetrated on it, Cucumovirus has succeed one of his objectives necessaries to commit the crime: entering to a vegetable cell. When staying inside it starts to uncoat, what implicates to release the viral nucleic acids from the capsid, liberating the viral genomic RNA into the cytoplasm, contained inside the virus cell sorrounded by the capsid; causing the expression of the first and second protein, what produces the recplication proteins, responsible for synthetising the RNA strands, in a viral factory, that can be different types of organelles, in concrete, the accomplice of giving home to this criminal is the vacuoles membrane or also called tonolpast. 

Image 4.3. Electronic micrscope
photo of a bascular bundle cells

And the crime starts! 
It produces a transcribement of the complete RNA genome, providing new viral RNA genomes in order to multiply the CMV to the whole plant, but it can really go somewhere alone? No, there must be something controlling it and this is not other than the capsid, a organelle that mantains everything to it position, so can, now, moves. Finally the viral movement protein triggers the formation of tubular structures called plasmodesmatas what allows the murderer to move from one host to the other next to it.

Image 4.4. Picture displaying the transport plasmodesmata system

But "when more you have, more you want", hence the Cucumovirus not happy by infecting mature cells, it transports cell-to-cell, traspassing different cells as Sclerenchyma, Collechyma, Parenchyma and Xyle, aiming to arrive to the phloem so can be transported easily to the green shots, his ambitious objective.

Image 4.5. Explicative picture of bascular bundle cells

CMV virus inoculation, let's make it slay

Before doing this experiment, it has to be done in a crop plant, in a controlled atmosphere (temperature of 22 degrees, humidity, containment), of Cucumis melo during 7 to 10 days so you dispose of a large number of youth individuals. Then you choose between most healthy melon plants.

Image. 5.1. Montse Martin working on the
selection of healthy melon plants

Image 5.2. Mixing green
shots in the mortar

After doing the selection with everything prepared, you proceed to extract a huge amount of virus contained in a pumpkin plant which has been yet infected with CMV, as it grants more efectiveness in the inoculation. To extract the Cucumovirus, you have to cut with an scalpel the green shoots (that contain most of the virus) and letting it sit in a mortar, you mix this part of the plant with coal and a phosphate buffer, and finally we grind it all together.

Image 5.3. Rubbing the Cucumis melo crop

We rub the youth plants, which had been before treated with an abrasive, with our fingers in an slowly way, the finger is wet with the virus solution, hence it is absorbed into the Cucumis melo from the scars (made by the rub of the abrasive).

Image 5.4. Watering melon
plants after being rubbed

When this is finished you wait for more or less thirty seconds and water it so CMV that has not entered in the plant, and is remaining in the superficial part of the melon plants goes away.