Molecular cloning and characterization of a newly identified member of the cadherin family, PB-cadherin.
We have isolated cDNA clones encoding novel proteins belonging to the cadherin family. These novel proteins are encoded by two distinct mRNA species generated by alternative splicing from a single gene, and based on preferential expression in the pituitary gland and brain, we named it PB-cadherin. One mRNA species encodes long type PB-cadherin composed of 803 amino acid residues with a longer cytoplasmic domain, whereas the other species encodes short-type PB-cadherin composed of 694 amino acid residues with a shorter cytoplasmic domain. Both long and short type PB-cadherin contain five repeats of a cadherin motif in the extracellular domain, the transmembrane domain, and the cytoplasmic domain, and the deduced amino acid sequences have a 30% homology to those of E-, N-, and P-cadherins. Although the primary structure of N-terminal amino acids is identical between long and short type PB-cadherin, the following structures in the cytoplasmic regions are completely different. The long type PB-cadherin but not the short type contains the putative catenin-binding domain. When these two distinct forms of PB-cadherins were stably expressed in L cells, L cells expressing long type PB-cadherin or short type PB-cadherin both acquired a Ca2+-dependent cell adhesion property, thereby indicating that both types of PB-cadherin are responsible for Ca2+-dependent cell adhesion. Persistent expression of PB-cadherin mRNA was found in the brain of rat embryos at least from embryonic day 15 to the postnatal period. In situ localization of PB-cadherin mRNA in the adult rat brain indicated that PB-cadherin mRNA is expressed in the inner granular layer of the olfactory bulb, Purkinje cell layer of the cerebellum, and in the pineal gland. PB-cadherin may play an important role in morphogenesis and tissue formation in neural and non-neural cells for the development and maintenance of the brain and neuroendocrine organs by regulating cell-cell adhesion.
Sugimoto
K
K
Division of Biochemistry, Osaka University Medical School, Japan.
Honda
S
S
Yamamoto
T
T
Ueki
T
T
Monden
M
M
Kaji
A
A
Matsumoto
K
K
Nakamura
T
T
D000375:Aging / Q000378:metabolism*; D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D001921:Brain / Q000378:metabolism; D015820:Cadherins / Q000096:biosynthesis* / Q000737:chemistry; D002645:Chickens; D003001:Cloning, Molecular; D017931:DNA Primers; D005314:Embryonic and Fetal Development; D005333:Fetus; D018507:Gene Expression Regulation, Developmental; D005865:Gestational Age; D017403:In Situ Hybridization; D007739:L Cells; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D016366:Open Reading Frames; D009928:Organ Specificity; D010902:Pituitary Gland / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D014162:Transfection
D015820:Cadherins; C504494:Cdh22 protein, mouse; C504493:Cdh22 protein, rat; D017931:DNA Primers; D012333:RNA, Messenger; D011994:Recombinant Proteins; C099417:CDH22 protein, human