Identification and characterization of novel calcium-binding proteins of Dictyostelium and their spatial expression patterns during development.
Five putative Ca2(+)-binding proteins, CBP5, 6, 7, 8 and 9, all having EF-hand motifs, were found by searching the Dictyostelium cDNA database (http://www.csm.biol.tsukuba.ac.jp/cDNAproject.html). 45Ca2(+)-overlay experiments revealed that four of these (excluding CBP9) are real Ca2(+)-binding proteins. Northern blot analysis revealed that the genes encoding CBP5, 6, 7 and 8 are all developmentally regulated. In situ hybridization analyses revealed that spatial expression of these genes was regulated in several different ways. CBP1, 2, 3, 5, 6 and 7 are expressed in prespore cells in the slug stage. Transcripts of the genes for CBP1 and 5 are enriched in prestalk subtype PstO cells. In contrast, CBP4 is expressed predominantly in PstO cells. CBP8 is evenly expressed at a very low level throughout the whole slug. Such distinct spatial expression patterns suggest that the CBP might be involved in morphogenesis and might have their own roles either in prespore or in prestalk cell differentiation of Dictyostelium.
Sakamoto
Haruyo
H
Department of Biology, Graduate School of Science, Osaka University, Machikaneyama-cho 1-16, Toyonaka, Osaka 560-0043, Japan.
Nishio
Keiko
K
Tomisako
Mariko
M
Kuwayama
Hidekazu
H
Tanaka
Yoshimasa
Y
Suetake
Isao
I
Tajima
Shouji
S
Ogihara
Satoshi
S
Coukell
Barrie
B
Maeda
Mineko
M
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D002118:Calcium / Q000737:chemistry / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002454:Cell Differentiation; D002460:Cell Line; D018076:DNA, Complementary / Q000378:metabolism; D019992:Databases as Topic; D004023:Dictyostelium / Q000166:cytology*; D018507:Gene Expression Regulation, Developmental; D005982:Glutathione Transferase / Q000378:metabolism; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010802:Phylogeny; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013997:Time Factors
D002135:Calcium-Binding Proteins; D018076:DNA, Complementary; D011993:Recombinant Fusion Proteins; D005982:Glutathione Transferase; D002118:Calcium