Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1988 Jan;85(1):208-12.
doi: 10.1073/pnas.85.1.208.

Isolation and structure of a cDNA encoding the B1 (CD20) cell-surface antigen of human B lymphocytes

T F Tedder  1 , M Streuli, S F Schlossman, H Saito
Affiliations

Isolation and structure of a cDNA encoding the B1 (CD20) cell-surface antigen of human B lymphocytes

T F Tedder et al. Proc Natl Acad Sci U S A. 1988 Jan.

Abstract

The B1 (CD20) molecule is a Mr 33,000 phosphoprotein on the surface of human B lymphocytes that may serve a central role in the humoral immune response by regulating B-cell proliferation and differentiation. In this report, a cDNA clone that encodes the B1 molecule was isolated and the amino acid sequence of B1 was determined. B-cell-specific cDNA clones were selected from a human tonsillar cDNA library by differential hybridization with labeled cDNA derived from either size-fractionated B-cell mRNA or size-fractionated T-cell mRNA. Of the 261 cDNA clones isolated, 3 cross-hybridizing cDNA clones were chosen as potential candidates for encoding B1 based on their selective hybridization to RNA from B1-positive cell lines. The longest clone, pB1-21, contained a 2.8-kilobase insert with an 891-base-pair open reading frame that encodes a protein of 33 kDa. mRNA synthesized from the pB1-21 cDNA clone in vitro was translated into a protein of the same apparent molecular weight as B1. Limited proteinase digestion of the pB1-21 translation product and B1 generated peptides of the same sizes, indicating that the pB1-21 cDNA encodes the B1 molecule. Gel blot analysis indicated that pB1-21 hybridized with two mRNA species of 2.8 and 3.4 kilobases only in B1-positive cell lines. The amino acid sequence deduced from the pB1-21 nucleotide sequence apparently lacks a signal sequence and contains three extensive hydrophobic regions. The deduced B1 amino acid sequence shows no significant homology with other known proteins.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Nature. 1970 Aug 15;227(5259):680-5 - PubMed
    1. Methods Enzymol. 1980;65(1):499-560 - PubMed
    1. Proc Natl Acad Sci U S A. 1985 Sep;82(18):6255-9 - PubMed
    1. J Mol Biol. 1977 Jun 15;113(1):237-51 - PubMed
    1. Proc Natl Acad Sci U S A. 1979 Aug;76(8):3683-7 - PubMed

Publication types

Associated data