Arrangement of centromeres in mouse cells

Studies on Thick Sections of the Nucleus of Mouse Sertoli Cells Using an Electron Microscope Operating at 300 kV

“…Their sizes varied and they sometimes contained vacuolar spaces of different sizes. Such findings agree with the observation of the previous workers (Hsu, 1971;Krimer, 1977) who chiefly used thin sections. Stereoscopic observation of thick sections revealed that two associated bodies were typically located on each side of a single nucleolus with relatively higher density than the nucleoli, while in the case of three bodies they formed triangular shape.…”

“…If was also suggested that centromeric heterochromatin is involved in the formation of these structures, showing hybridization of satellite DNA in the perinucleolar bodies (Krimer, 1977). In a study reported by Hsu et al (1971), it was noted that in mouse Sertoli cells, neurons, and spermatids, all paracentromeric heterochromatin aggregated in one area or in a few neighboring areas. They also reverled that an average of four heterochromatin blOcks were found in Sertoli cell nucleoli, which is so fewer than that in immature cell types.…”

Ultrastructural features of minute chromosomes in a methotrexate-resistant mouse 3T3 cell line

“…2). An interesting hypothesis for the basis of the minute chromosome associations in the 3T3 R500 cells is that they reflect the presence of sequences of the amplified DNA in at least some of the minute chromosomes in this cell line that have sequence homology with chromosomes, similar to heterochromatin associations of normal chromosomes (31), and that such DNA sequences are not, or are rarely, present in minutes of the 3T6 R50 cell line. With appropriate probes, this possibility is testable using in situ hybridization.…”

Centromeric ring and arrangement of centromeres in interphase of Lathyrus sphaericus as detected by C-banding.

“…Previous data on cytology (Avivi and Feldman 1980), autoradiography (Fussell 1975), electron microscopy (Church and Moens 1976) and banding (Stack and Clark 1974, Fussell 1977, Ghosh and Roy 1977, Tanaka and Tanaka 1977, Lavania and Sharma 1980b) studies on a variety of plants show that interphase chromosomes retain their telophase arrange ment. However, Hsu et al (1971) found that position of centromeres in the in terphase nucleus of Mus musculus varied from tissue to tissue . Fussell (1977) sug gested that telophase orientation of interphase chromosomes is typical of cells with high mitotic rates.…”