Identification of two noncanonical members to the CCp gene family of Babesia bovis and Babesia bigemina

Primary author: Sezayi OZUBEK
Co-author(s): Heba F. Alzan; Reginaldo G. Bastos; Carlos E. Suarez
Faculty sponsor: Carlos Suarrez; Scientific and Technological Research Council of Turkey(TUBITAK)

Primary college/unit: College of Veterinary Medicine
Campus: Pullman

Abstract:

Babesia bovis and B. bigemina are responsible for bovine babesiosis, a tick borne disease that causes important economic losses in many tropical and semi-tropical regions worldwide. The CCp protein family, containing LCCL motifs, is differentially expressed on gametocytes of apicomplexans, including Plasmodium and Babesia. Knocking out Plasmodium CCp genes blocks development of the parasite in the mosquito vector, making the CCp proteins potential targets for transmission-blocking vaccines. Although six LCCL protein family members (CCp1-5 and FNPA) have been identified in Plasmodium falciparum, only genes encoding for homologous of the CCp1-3 proteins have so far been reported in B. bovis and B. bigemina. In this study, we describe the presence of two additional CCp-related genes (CCp5 and FNPA) in the genomes of B. bovis and B. bigemina. Similar to other apicomplexan CCp proteins, the newly identified CCp proteins also have a signal peptide (B. bigemina CCp5 and FNPA) and a transmembrane domain (B. bovis FNPA), consistent with surface expression. Consistent with their putative role during sexual reproduction of the parasite in the tick gut, RNAseq analysis sugests that none of the CCp genes are highly expressed in the blood stage, and at negligible levels in kinete stages. The pattern of expression of the new CCp members during distinct developmental stages of B. bovis and B. bigemina will be explored in further studies.