Coilin is essential for Cajal body organization in Drosophila melanogaster.
Cajal bodies (CBs) are nuclear organelles that occur in a variety of organisms, including vertebrates, insects, and plants. They are most often identified with antibodies against the marker protein coilin. Because the amino acid sequence of coilin is not strongly conserved evolutionarily, coilin orthologues have been difficult to recognize by homology search. Here, we report the identification of Drosophila melanogaster coilin and describe its distribution in tissues of the fly. Surprisingly, we found coilin not only in CBs but also in histone locus bodies (HLBs), calling into question the use of coilin as an exclusive marker for CBs. We analyzed two null mutants in the coilin gene and a piggyBac insertion mutant, which leads to specific loss of coilin from the germline. All three mutants are homozygous viable and fertile. Cells that lack coilin also lack distinct foci of other CB markers, including fibrillarin, the survival motor neuron (SMN) protein, U2 small nuclear RNA (snRNA), U5 snRNA, and the small CB-specific (sca) RNA U85. However, HLBs are not obviously affected in coilin-null flies. Thus, coilin is required for normal CB organization in Drosophila but is not essential for viability or production of functional gametes.
Liu
Ji-Long
JL
Carnegie Institution, Department of Embryology, Baltimore, MD 21218, USA.
Wu
Zheng'an
Z
Nizami
Zehra
Z
Deryusheva
Svetlana
S
Rajendra
T K
TK
Beumer
Kelly J
KJ
Gao
Hongjuan
H
Matera
A Gregory
AG
Carroll
Dana
D
Gall
Joseph G
JG
D000375:Aging / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D002453:Cell Cycle; D020541:Coiled Bodies / Q000378:metabolism*; D017124:Conserved Sequence; D004331:Drosophila melanogaster / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006657:Histones / Q000378:metabolism; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010053:Ovary / Q000378:metabolism; D016415:Sequence Alignment; D013737:Testis / Q000378:metabolism
D006657:Histones; D009687:Nuclear Proteins; C068921:p80-coilin