Centric fusions from primary cell culture of calf kidney applied to chromosomal evolution, conservation and speciation in the bovidae family

Abstract

The aim of this study was to clarify the chromosomal evolution and alterations by using continuous primary cell cultures of Calf Kidney during different Passages. In order to investigate, we studied incidence of chromosome fusions with the consecutive subcultivations and G-banding method. Kidney primary cell culture of Holstein cattle was investigated during several primary Passages (up to 30), but no changes were observed (2n=60). At Passage 32, two acrocentric chromosomes were attached from centromere; therefore the diploid chromosome number (2n) became 59. The observations of chromosomal rearrangements were studied in Passage 42 (2n=58), Passage 50 (2n=56 (70%), 2n=54 (20%), 2n=52 (10%)), Passage 55 (2n=54 (60%), 2n=52 (40%)), Passage 60 (2n= 48 (80%)).However, the number of autosomal arms (NAA) was 58 during all Passages. After Passage 65, kidney primary cells that have proliferated in cell culture for several months, appear genetically normal are referred to as cell lines. A decrease in the number of acrocentric chromosomes was followed by constitution of (sub) metacentric chromosomes. According to the novel horizon, our results suggest that evolutionary processes show a decrease in chromosome number from 2n=60 to 2n=48; on the other hand, acrocentric chromosomes tend to form (sub) metacentric chromosomes by chromosome fusion; however, with constant NAA specified for each family of mammals. Therefore, NAA is a distinctive marker for detection of the mammalian positions of classification. © 2008 Springer-Verlag.