Assembly of IMPDH2-Based, CTPS-Based, and Mixed Rod/Ring Structures Is Dependent on Cell Type and Conditions of Induction

Autor(es)

Keppeke, Gerson Dierley ^{[1, 2]} ; John Calise, S. ^[1] ; Chan, Edward K. L. ^[1] ; Andrade, Luis Eduardo C. ^{[2, 3]}

Afiliação do(s) autor(es)

^[1] Univ Florida, Dept Oral Biol, Gainesville, FL 32610 - USA

^[2] Univ Fed Sao Paulo, Div Rheumatol, BR-04023062 Sao Paulo, SP - Brazil

^[3] Fleury Med & Hlth Labs, Div Immunol, BR-04102050 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF GENETICS AND GENOMICS; v. 42, n. 6, p. 287-299, JUN 20 2015.
• Citações Web of Science: 19

Resumo

Inhibition of guanosine triphosphate (GTP) and cytidine triphosphate (CTP) biosynthetic pathways induces cells to assemble rod/ring (RR) structures, also named cytoophidia, which consist of the enzymes cytidine triphosphate synthase (CTPS) and inosine-5'-monophosphate dehydrogenase 2 (IMPDH2). We aim to explore the interaction of CTPS and IMPDH2 in the generation of RR structures. HeLa and COS-7 cells were cultured in normal conditions or in the presence of 6-diazo-5-oxo-L-norleucine (DON), ribavirin, or mycophenolic acid (MPA). Over 90% of DON-treated cells presented RR structures. In HeLa cells, 35% of the RR structures were positive for IMPDH2 alone, 26% were CTPS alone, and 31% were IMPDH2/CTPS mixed, while in COS-7 cells, 42% of RR were IMPDH2 alone, 41% were CTPS alone, and 10% were IMPDH2/CTPS mixed. Ribavirin and MPA treatments induced only IMPDH2-based RR. Cells were also transfected with an N-terminal hemagglutinin (NHA)-tagged CTPS1 construct. Over 95% of NHA-CTPS1 transfected cells with DON treatment presented IMPDH2-based RR and almost 100% presented CTPS1-based RR; when treated with ribavirin, over 94% of transfected cells presented IMPDH2-based RR and 37% presented CTPS1-based RR, whereas 2% of untreated transfected cells presented IMPDH2-based RR and 28% presented CTPS1-based RR. These results may help in understanding the relationship between CTP and GTP biosynthetic pathways, especially concerning the formation of filamentous RR structures. (AU)

• Processo FAPESP: 11/12448-0 - Anticorpos anti-"Rods & Rings", HCV e ribavirina/interferon: um Modelo Humano de Geração de Autoanticorpos
• Beneficiário: Gerson Dierley Keppeke
• Modalidade de apoio: Bolsas no Brasil - Doutorado