Chromosomal traits of Chamaelirium luteum (Melanthiaceae) with particular focus on the large heterochromatic centromeres

Noriyuki TANAKA

《TAIWANIA》 65卷3期 (2020/09) Pp. 286-294

https://doi.org/10.6165/tai.2020.65.286

摘要

Chromosomal morphology and behavior during the mitotic cell cycle and properties as to the DNA base composition in heterochromatin of Chamaelirium luteum from eastern North America were investigated by conventional and fluorescent banding methods. The chromosomes proved to have no primary constrictions; instead, they had unusually large heterochromatic monocentromeres termed ＂macrocentromeres＂ that were as thick as the chromosome arms and tended to protrude poleward at metaphase. It also became evident that the centromeres are rich in AT base pairs, whereas the satellites are GC-rich. Data suggested that the centromeric domains were tightly compacted almost through the cell cycle and situated at the nuclear periphery during telophase, interphase and prophase. The roles of centromeres and their causality to the property of centromeric DNA were discussed briefly. Some chromosomal traits of C. luteum were compared with those known for Asian congeners reported to have holocentromeres.

關鍵字

Centromeric DNA ； Chionographis ； Fluorescent chromosome banding ； Holocentromere ； Karyotype ； Macrocentromere

參考文獻

Tanaka, N. 2017. A synopsis of the genus Chamaelirium (Melanthiaceae) with a new infrageneric classification including Chionographis. Taiwania 62(2): 157–167.

Behr, W., K. Honikel and G. Hartmann. 1969. Interaction of the RNA polymerase inhibitor Chromomycin with DNA. Eur. J. Biochem. 9(1): 82–92.

Comings, D.E. 1975. Mechanisms of chromosome banding VIII. Hoechst 33258-DNA interaction. Chromosoma 52(3): 229–243.

Comings, D.E. and M.E. Drets. 1976. Mechanisms of chromosome banding IX. Are variations in DNA base composition adequate to account for quinacrine, Hoechst 33258 and daunomycin banding? Chromosoma 56(3): 199–211.

Cuacos, M., F.C. Franklin and S. Heckmann. 2015. Atypical centromeres in plants - what they can tell us. Front. Plant Sci. 6: 913.