Identification and cloning of the SNARE proteins VAMP-2 and syntaxin-4 from HL-60 cells and human neutrophils.
Degranulation and membrane fusion by neutrophils are essential to host defense. We sought homologues of neuron-specific fusion proteins in human neutrophils and in their precursors, the promyelocytic cell line HL-60. We screened a differentiated HL-60 library and obtained an 848 bp sequence with a 351 bp open reading frame, identical to that published for human VAMP-2 and including 5' and 3' untranslated regions. RNA from HL-60 cells during differentiation into the neutrophil lineage was subjected to Northern blot analysis. which revealed a transcript of approximately 1050 bp at all stages of differentiation. The amount of these transcripts increased approximately threefold during differentiation, a finding confirmed by quantitative RT-PCR. We also detected mRNA for VAMP-2 in human neutrophils and monocytes using RT-PCR. In like fashion, transcripts of syntaxin-4, another fusion protein, were recovered from a neutrophil cDNA library. As with VAMP-2, expression of syntaxin-4 (determined by Northern blots) also increased, but by only 50%, during differentiation of HL-60 cells. These studies demonstrate that neutrophils and their progenitors possess mRNA for the fusion proteins VAMP-2 and syntaxin-4, and that their transcription increases during differentiation, concurrent with the functional maturation of myeloid cells.
Smolen
J E
JE
Department of Pediatrics, Leukocyte Biology Section, Baylor College of Medicine, Houston, Texas 77030-2600, USA. jsmolen@bcm.tmc.edu
Hessler
R J
RJ
Nauseef
W M
WM
Goedken
M
M
Joe
Y
Y
D002454:Cell Differentiation / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D006098:Granulocytes / Q000166:cytology / Q000378:metabolism*; D018922:HL-60 Cells; D006801:Humans; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000235:genetics; D009504:Neutrophils / Q000166:cytology / Q000378:metabolism*; D050765:Qa-SNARE Proteins; D050683:R-SNARE Proteins; D012333:RNA, Messenger / Q000032:analysis; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins
D018076:DNA, Complementary; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D050765:Qa-SNARE Proteins; D050683:R-SNARE Proteins; D012333:RNA, Messenger; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins