Acta Parasitologica

, Volume 64, Issue 2, pp 262–267 | Cite as

Sequence Analysis of the cAMP-Dependent Protein Kinase Regulatory Subunit-Like Protein From Trypanosoma brucei

  • Nelson A. AraujoEmail author
  • José Bubis
Research note



Study the N-terminal, C-terminal, and linker regions of the TbPKAr using homology modeling.


The amino acid sequences of the N-terminal, C-terminal, and linker regions of the TbPKAr were individually examined by means of BLAST analysis and in silico secondary structure predictions with several programs.


The TbPKAr C-terminal region, showed a well-folded α/β structure, which consists of two concurrent flattened β-barrel-shaped domains that are separated by an elongated central α-helix similar to its mammalian counterpart, the TbPKAr linker region contains a PKA phosphorylation site and was predicted to be rather disordered. Our analysis also indicated that the TbPKAr N-terminal region lacks a docking/dimerization domain but is enriched in motifs known as leucine-rich repeats (LRR).


The replacement of the docking/dimerization domain by different structural motifs suggests the inability of TbPKAr to form homodimers; however, the function of the TbPKAr N-terminal LRR-containing domain in Kinetoplastidae parasites is still unknown.


Trypanosoma brucei cAMP-dependent protein kinase PKA Regulatory subunits Leucine-rich repeats Structure prediction 



The authors thank Juan Ricardo Rodrigues for his very useful comments and for reviewing an initial draft of the manuscript. This research was supported by Grant numbers S1-IN-CB-002-17 from Decanato de Investigación y Desarrollo, Universidad Simón Bolívar, Caracas, Venezuela, and 2013001659 from FONACIT, Caracas, Venezuela.


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Copyright information

© Witold Stefański Institute of Parasitology, Polish Academy of Sciences 2019

Authors and Affiliations

  1. 1.Laboratorio de Caracterización de Proteínas, Departamento de Biología CelularUniversidad Simón BolívarCaracasVenezuela
  2. 2.Laboratorio de Química de Proteínas, Departamento de Biología CelularUniversidad Simón BolívarCaracasVenezuela

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