“TRANSMISSION BY INSECTS OF THE Papaya meleira virus COMPLEX (PMeV and PMeV2) AND PROSPECTION AND CHARACTERIZATION OF A FRACTION OF THE STRUCTURAL PROTEIN OF PMeV”
Name: JOELLINGTON MARINHO DE ALMEIDA
Publication date: 06/05/2024
Examining board:
Name |
Role |
|---|---|
| ALEXANDRE MARTINS COSTA SANTOS | Coorientador |
| ANDRE DA SILVA XAVIER | Examinador Externo |
| JOSE AIRES VENTURA | Examinador Interno |
| MARLONNI MAURASTONI ARAÚJO | Examinador Externo |
| PATRICIA MACHADO BUENO FERNANDES | Presidente |
Pages
Summary: Papaya sticky disease caused by a virus that can lead to a loss of productivity in Carica papaya orchards in the main producing countries, such as Brazil, Mexico, Ecuador and Australia. Infection of the plant causes burning of young leaves, spontaneous exudation of latex and spots on the fruit. The oxidation of the latex in contact with the air gives rise to a "honeyed" appearance, which together with other factors interferes with the marketing of the fruit. However, the vector that causes the disease is not yet known in all producing countries. Studies carried out by various research groups have pointed to an airborne vector as a potential disseminator of the disease, as well as the phylogenetic relationship of the virus with endophytic fungi and its transmission through seeds of papaya plants. In Brazil, it is caused by the viral complex papaya meleira virus (PMeV) and papaya meleira virus 2 (PMeV2), and the coexistence of the two viruses has proven that PMeV2 is encapsidated by PMeV, and it is known that PMeV has two open reading frames (ORFs) responsible for encoding structural proteins that make up the capsid (ORF1) and a putative RdRp protein (ORF2). Knowing that the structural proteins of PMeV are responsible for encapsidating the two genetic materials, using the expression of a fraction of the recombinant protein of the PMeV capsid protein (CP) may become viable in the development of rapid tests, identification of viral particles in different locations of the plant and potential application in virus-plant-vector transmission studies. In the present study, the development of material on understanding possible means of viral transmission of the papaya meleira virus complex was carried out using the available literature, associating how the development of rapid diagnostic tests can help in the detection of the virus in the plant and in other organisms. Thus, a fraction of the PMeV capsid protein was expressed in E. coli BL21(DE3) and extracted from the SDS-PAGE gel. The protein fraction was expressed in four times (30 minutes, 1 hour, 2 hours and 4 hours) to verify which would correspond to its highest production and its extracted fraction led to the production of polyclonal antibodies. From the available sequence, an in silico characterization was carried out to verify its amino acid composition, three-dimensional structure, physicochemistry and prediction of immunogenic peptides possible to be identified in its primary sequence. The results obtained enable the design of an effective rapid test and the use of antibodies that can be applied in future studies of virus localization in different parts of the plant.
