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K LaMarco

Publications and source records attributed to K LaMarco.

4 recordsLinked to original sources

The VP16 accessory protein HCF is a family of polypeptides processed from a large precursor protein.

Upon lytic infection of permissive cells, the herpes simplex virus (HSV) transactivator protein VP16 associates with an accessory protein termed host cell factor (HCF). Binding to HCF activates VP16 for association with the octamer motif-binding protein Oct-1, to form a multiprotein-DNA complex responsible for activating transcription of the HSV immediate early genes. We show that HCF comprises a series of related polypeptides that range from 110 to 300 kd, all of which are encoded by a single gene. Although there is no obvious sequence similarity between HCF and other known proteins, HCF contains eight repeats of a new 26 amino acid motif. cDNAs encoding HCF predict a large open reading frame of 2035 codons. When expressed in human cells, this large open reading frame encodes both the 300 kd and smaller HCF polypeptides, indicating that the smaller polypeptides arise by processing of the 300 kd protein.

Amino Acid Sequence

Identification of Ets- and notch-related subunits in GA binding protein.

Recombinant cDNA clones that encode two distinct subunits of the transcription factor GA binding protein (GABP) have been isolated. The predicted amino acid sequence of one subunit, GABP alpha, exhibits similarity to the sequence of the product of the ets-1 protooncogene in a region known to encompass the Ets DNA binding domain. The sequence of the second subunit, GABP beta, contains four 33-amino acid repeats located close to the NH2-terminus of the subunit. The sequences of these repeats are similar to repeats in several transmembrane proteins, including Notch from Drosophila melanogaster and Glp-1 and Lin-12 from Caenorhabditis elegans. Avid, sequence-specific binding to DNA required the presence of both polypeptides, revealing a conceptual convergence of nuclear transforming proteins and membrane-anchored proteins implicated in developmentally regulated signal transduction processes.

Amino Acid Sequence