Hhq. Heng et al., REGULATION OF MEIOTIC CHROMATIN LOOP SIZE BY CHROMOSOMAL POSITION, Proceedings of the National Academy of Sciences of the United Statesof America, 93(7), 1996, pp. 2795-2800
At meiotic prophase, chromatin loops around a proteinaceous core, with
the sizes of these loops varying between species, Comparison of the m
orphology of sequence-related inserts at different sites in transgenic
mice demonstrates that loop size also varies with chromosomal geograp
hy, Similarly, chromatin loop lengths differ dramatically for intersti
tially and terminally located hamster telomeric sequences, Sequences,
telomeric or otherwise, located at chromosome termini, closely associa
te with the meiotic proteinaceous core, forming shorter loops than ide
ntical interstitial sequences, Thus, we present evidence that differen
t chromatin packaging mechanisms exist for interstitial versus termina
l chromosomal regions, which act separately from those operating at th
e level of the DNA sequence, Chromosomal position plays the dominant r
ole in chromatin packaging.