Knockdown of the Plasmodium falciparum SURFIN4.1 antigen leads to an increase of its cognate transcript

Author(s)

Macedo-Silva, Tatiane ; Duque Araujo, Rosana Beatriz ; Meissner, Kamila Anna ; Fotoran, Wesley Luzetti ; Medeiros, Marcia Melo ; de Azevedo, Mauro Ferreira ; Wunderlich, Gerhard

• Document type: Journal article
• Source: PLoS One; v. 12, n. 8 AUG 11 2017.
• Web of Science Citations: 0

Abstract

The genome of the malaria parasite Plasmodium falciparum contains the surf gene family which encodes large transmembrane proteins of unknown function. While some surf alleles appear to be expressed in sexual stages, others occur in asexual blood stage forms and may be associated to virulence-associated processes and undergo transcriptional switching. We accessed the transcription of surf genes along multiple invasions by real time PCR. Based on the observation of persistent expression of gene surf4.1, we created a parasite line which expresses a conditionally destabilized SURFIN4.1 protein. Upon destabilization of the protein, no interference of parasite growth or morphological changes were detected. However, we observed a strong increase in the transcript quantities of surf4.1 and sometimes of other surf genes in knocked-down parasites. While this effect was reversible when SURFIN4.1 was stabilized again after a few days of destabilization, longer destabilization periods resulted in a transcriptional switch away from surf4.1. When we tested if a longer transcript half-life was responsible for increased transcript detection in SURFIN4.1 knocked-down parasites, no alteration was found compared to control parasite lines. This suggests a specific feedback of the expressed SURFIN protein to its transcript pointing to a novel type of regulation, inedited in Plasmodium. (AU)

• FAPESP's process: 15/17174-7 - Factors influencing expression of variant antigen families var, rif and surf of Plasmodium falciparum, the human malaria parasite
• Grantee: Gerhard Wunderlich
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/23306-5 - Studies on the mechanism of transcriptional control and switching of virulence-associated genes in Plasmodium falciparum
• Grantee: Gerhard Wunderlich
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/12439-7 - Studies on the mode of transcription and expression of surf genes from Plasmodium falciparum
• Grantee: Tatiane Macedo Silva
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 15/19316-3 - Regulation of P. falciparum egress from the host cell: identification of new targets
• Grantee: Mauro Ferreira de Azevedo
• Support Opportunities: Research Grants - Young Investigators Grants