Biochemical and Biophysical Research Communications
Two forms of human Inscuteable-related protein that links Par3 to the Pins homologues LGN and AGS3☆
Section snippets
Materials and methods
Isolation of cDNAs for human Insc. A search of EST databases with a nucleotide region encoding amino acids 539–593 of Drosophila Insc yielded a human EST clone (BQ675721) that encodes amino acids 211–579 of a novel protein, and subsequently another human EST clone (BU147420) that contains amino acids 48–561 of the novel protein. Based on sequences of the EST clones, we synthesized the two unique oligonucleotide primers 5′-GCGGATCCAGTTTCCGGTGCTTGTACCC-3′ (forward primer) and 5′-GCGAATTCA
Primary structure of human Inscuteable
On the basis of sequences of EST clones exhibiting similarities to Drosophila Insc, we cloned cDNAs for human homologue of Insc (for detail, see Materials and methods). We obtained two distinct forms of the transcripts: one encodes 579 amino acids, tentatively designated the long form (GenBank Accession No. AB236159); and the other encodes the short form of 532 amino acids (GenBank Accession No. AB236158), which lacks the N-terminal 47 amino acids (Fig. 1A). In the C-terminal half, human Insc
Concluding remarks
In the present study, we have identified the two forms of the human Insc transcript: the Insc gene is differentially expressed from alternative first exons. The long form encodes 579 amino acids, whereas the short one lacks the N-terminal 47 amino acids (Fig. 1, Fig. 2); and tissue expression pattern of the long form is different from that of the short form (Fig. 3). Both forms of human Insc can interact with the human Pins homologues LGN and AGS3 (Fig. 4A), and with human Par3 and its related
Acknowledgments
We are grateful to Miki Matsuo (Kyushu University), Yohko Kage (Kyushu University and JST), Natsuko Yoshiura (Kyushu University), and Namiko Kubo (Kyushu University and JST) for technical assistance, and to Minako Nishino (Kyushu University and JST) for secretarial assistance. This work was supported in part by Grants-in-Aid for Scientific Research and National Project on Protein Structural and Functional Analyses from the Ministry of Education, Culture, Sports, Science and Technology of Japan,
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Abbreviations: aPKC, atypical protein kinase C; Gα, the α subunit of trimeric G protein; Pins, Partner of Inscuteable; Insc, Inscuteable; PCR, polymerase chain reaction; 5′-RACE, 5′-rapid amplification of cDNA ends.