A three-dimensional view of precursor messenger RNA metabolism within the mammalian nucleus.
A quantitative three-dimensional analysis of nuclear components involved in precursor messenger RNA metabolism was performed with a combination of fluorescence hybridization, immunofluorescence, and digital imaging microscopy. Polyadenylate [poly(A)] RNA-rich transcript domains were discrete, internal nuclear regions that formed a ventrally positioned horizontal array in monolayer cells. A dimmer, sometimes strand-like, poly(A) RNA signal was dispersed throughout the nucleoplasm. Spliceosome assembly factor SC-35 localized within the center of individual domains. These data support a nuclear model in which there is a specific topological arrangement of noncontiguous centers involved in precursor messenger RNA metabolism, from which RNA transport toward the nuclear envelope radiates.
Carter
K C
KC
Department of Cell Biology, University of Massachusetts Medical Center,Worcester 01655.
Bowman
D
D
Carrington
W
W
Fogarty
K
K
McNeil
J A
JA
Fay
F S
FS
Lawrence
J B
JB
D002467:Cell Nucleus / Q000378:metabolism*; D006801:Humans; D008856:Microscopy, Fluorescence; D009685:Nuclear Envelope / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D011061:Poly A / Q000378:metabolism; D012322:RNA Precursors / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D017411:Ribonucleoproteins, Small Nuclear / Q000378:metabolism
D009687:Nuclear Proteins; D012322:RNA Precursors; D012333:RNA, Messenger; D017411:Ribonucleoproteins, Small Nuclear; D011061:Poly A