Interaction of a potential vacuolar targeting receptor with amino- and carboxyl-terminal targeting determinants

Plant Physiol. 1996 Jun;111(2):469-74. doi: 10.1104/pp.111.2.469.

Abstract

A protein of 80 kD from developing pea (Pisum sativum) cotyledons has previously been shown to exhibit characteristics of a vacuolar targeting receptor by means of its affinity for the amino-terminal vacuolar targeting sequence of proaleurain from barley (Hordeum vulgare). In this report we show that the same protein also binds to the amino-terminal targeting peptide of prosporamin from sweet potato (Ipomoea batatas) and to the carboxyl-terminal targeting determinant of pro-2S albumin from Brazil nut (Bertholletia excelsa). The receptor protein does not bind to the carboxyl-terminal propeptide (representing the targeting sequence) of barley lectin. The binding of the 80-kD protein to the sporamin determinant involves a motif (NPIR) that has been shown to be crucial for vacuolar targeting in vivo. The binding to the carboxyl-terminal targeting determinant of pro-2S albumin appears to involve the carboxyl-terminal propeptide and the adjacent five amino acids of the mature protein. The 80-kD protein does not bind to peptide sequences that have been shown to be incompetent in directing vacuolar targeting.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Binding Sites / genetics
  • Molecular Sequence Data
  • Molecular Weight
  • Plant Proteins / chemistry
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism*
  • Plants / genetics
  • Plants / metabolism
  • Prealbumin / genetics
  • Prealbumin / metabolism
  • Protein Binding
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Vacuoles / metabolism*

Substances

  • Plant Proteins
  • Prealbumin
  • Receptors, Cytoplasmic and Nuclear
  • sporamin protein, Ipomoea batatas