title: The telomerase reverse transcriptase subunit from the dimorphic fungus Ustilago maydis.
abstract: In this study, we investigated the reverse transcriptase subunit of telomerase in the dimorphic fungus Ustilago maydis. This protein (Trt1) contains 1371 amino acids and all of the characteristic TERT motifs. Mutants created by disrupting trt1 had senescent traits, such as delayed growth, low replicative potential, and reduced survival, that were reminiscent of the traits observed in est2 budding yeast mutants. Telomerase activity was observed in wild-type fungus sporidia but not those of the disruption mutant. The introduction of a self-replicating plasmid expressing Trt1 into the mutant strain restored growth proficiency and replicative potential. Analyses of trt1 crosses in planta suggested that Trt1 is necessary for teliospore formation in homozygous disrupted diploids and that telomerase is haploinsufficient in heterozygous diploids. Additionally, terminal restriction fragment analysis in the progeny hinted at alternative survival mechanisms similar to those of budding yeast.
authors.affiliation: Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico.
authors.forename: Dolores
authors.initials: D
authors.lastname: Bautista-España
authors.affiliation: Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico.
authors.forename: Estela
authors.initials: E
authors.lastname: Anastacio-Marcelino
authors.affiliation: Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Horta-Valerdi
authors.affiliation: Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico.
authors.forename: Antonio
authors.initials: A
authors.lastname: Celestino-Montes
authors.affiliation: Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia.
authors.forename: Milorad
authors.initials: M
authors.lastname: Kojic
authors.affiliation: Facultad de Estudios Superiores Iztacala, UNAM, Los Reyes Iztacala, Tlalnepantla, Estado de Mexico, Mexico.
authors.forename: Erasmo
authors.initials: E
authors.lastname: Negrete-Abascal
authors.affiliation: Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico.
authors.forename: Hortensia
authors.initials: H
authors.lastname: Reyes-Cervantes
authors.affiliation: Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico.
authors.forename: Candelario
authors.initials: C
authors.lastname: Vázquez-Cruz
authors.affiliation: Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados, Irapuato, Guanajuato, Mexico.
authors.forename: Plinio
authors.initials: P
authors.lastname: Guzmán
authors.affiliation: Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico.
authors.forename: Patricia
authors.initials: P
authors.lastname: Sánchez-Alonso
mesh_terms: D000595:Amino Acid Sequence; D004261:DNA Replication / Q000235:genetics; D004171:Diploidy; D015966:Gene Expression Regulation, Fungal; D013170:Spores / Q000235:genetics; D019098:Telomerase / Q000096:biosynthesis* / Q000235:genetics* / Q000302:isolation & purification; D014588:Ustilago / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development
chemical_list: D019098:Telomerase