小熊猫染色体异染色质的显示

以培养的小熊猫外周淋巴细胞为实验材料，结合Ｃ－显带技术及ＣＭＡ３／ＤＡ／ＤＡＰＩ三竽荧光杂色的方法，对小熊猫的染色体组型、Ｃ－带带型及ＣＭＡ３／ＤＡ／ＤＡＰＩ荧光带带型进行了研究，发现：（１）经Ｃ－显带技术处理，可在小熊猫染色体上呈现出一种极为独特的Ｃ－带带型。在多数染色体上可见到丰富的插入Ｃ－带及端粒Ｃ－带。而着丝区仅显示弱阳性Ｃ－带；（２）除着丝粒区外，ＣＭＡ３诱导的大多数强荧光带纹与Ｃ－阳性

HETEROCHROMATIN DEMONSTRATION IN THE CHROMOSOMES OF RED PANDA (AILURUS FULGENS)

The heterochromatin of Red panda's chromosomes were extensively studied with regional banding methods. It has been found that:(1) With C-banding technique, the Red panda's chromosomes display a very special C-banding pattern. A lot of strong posltlve lntercalary C-bands and telomeric C-bands on most chromosomes of Red panda can be observed, while the centromeric C-bands is very rare or non-exist in the centromeric regions. (2) When chromosome stained with the fluorescent dyes chromomycin A,(CMA3) and distamycin A/DAPI which label different subsets of heterochromatin in the chromosome complement, the bright fluorescence CMA3-bands which contain mainly GC rich DNA appear on telomeric regions and arms of most chromosomes of Red panda. But on the centromeric regions of most chromosomes, only fewer weak fluorescence CMA2-bands can be observed. There is no differentiated distamycin A/DAPI banding pattern which can be found when stained chromosomes are irradiated with UV light.(3) Most bright fluorescence CMA3-bands are accordant with the positive C-bands, this suggests that these positove C-bands of Red panda's chromosomes are rich in GC base pairs.(4) Chromosome 14, with a secondary constriction on the short arm, is a metacentric chromosome. Only this marker chromosome of Red panda display a very strong positive centromeric C-band which is very similar to that of giant panda's marker chromosome.