Selective expression of vacuolar H+-ATPase subunit d2 by particular subsets of dendritic cells among leukocytes.
Dendritic cells (DC) are far more potent to activate T cells than other antigen presenting cells (e.g., macrophages) and distributed to many organs where DC develop to functionally and phenotypically distinctive subsets. To isolate DC-differentially expressed genes, we used a subtractive cDNA cloning (XS52 DC minus J774 macrophages), resulting in the identification of d2 isoform of vacuolar (V) H+-ATPase subunit d. Unlike the ubiquitously expressed isoform (d1), d2 mRNA manifested expression restricted to particular subsets of DC (e.g., skin- and bone marrow-derived DC) among leukocytes and encoded two transcripts (1.6 and 3.0 kb) that differed in the length of the 3'-untranslated region. The d2 protein displayed association with membranes and the localization in lysosomes and antigen-containing endosomes. Interestingly, XS52 DC expressed seven-fold higher V-ATPase proton-pump activity than J774 macrophages and distinguished from the macrophage by high levels of isoforms a1 and a2 expression among V-ATPase subunits. These results indicated that d2 is a new marker for DC and it may, co-operatively with subunit a isoforms, regulate V-ATPase activity.
Sato
Kota
K
Department of Dermatology, The University of Texas Southwestern Medical Center, Dallas Veterans Affairs Medical Center, 5323 Harry Hines Building, Dallas, TX 75390-9069, USA.
Shikano
Sojin
S
Xia
Guohong
G
Takao
Joe
J
Chung
Jin-Sung
JS
Cruz
Ponciano D
PD
Xie
Xiao-Song
XS
Ariizumi
Kiyoshi
K
D000818:Animals; D017951:Antigen Presentation; D001483:Base Sequence; D002460:Cell Line; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D003713:Dendritic Cells / Q000145:classification / Q000201:enzymology* / Q000276:immunology*; D011992:Endosomes / Q000201:enzymology / Q000276:immunology; D015870:Gene Expression; D066298:In Vitro Techniques; D007962:Leukocytes / Q000145:classification / Q000201:enzymology / Q000276:immunology; D008213:Lymphocyte Activation; D008264:Macrophages / Q000201:enzymology / Q000276:immunology; D008566:Membranes / Q000201:enzymology; D051379:Mice; D021122:Protein Subunits; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology; D025262:Vacuolar Proton-Translocating ATPases / Q000737:chemistry* / Q000235:genetics*
D018076:DNA, Complementary; D021122:Protein Subunits; D012333:RNA, Messenger; D025262:Vacuolar Proton-Translocating ATPases