Occurrence of five different chromosomal HMG1 proteins in various maize tissues

• Published in: Plant molecular biology Vol. 41; no. 3; pp. 351 - 361
• Main Authors: Stemmer, C, Grimm, R, Grasser, K.D
• Format: Journal Article
• Language: English
• Published: Netherlands Springer Nature B.V 01.10.1999
• Subjects: Amino Acid Sequence; amino acid sequences; Base Sequence; cell suspension culture; Cells, Cultured; chromatin; Cloning; Cloning, Molecular; complementary DNA; Corn; DNA, Complementary - genetics; DNA-binding proteins; genbank/aj006708; half life; high mobility group proteins; High Mobility Group Proteins - genetics; High Mobility Group Proteins - isolation & purification; High Mobility Group Proteins - metabolism; leaves; Molecular Sequence Data; molecular weight; nucleotide sequences; Plant Leaves - chemistry; Plant Leaves - genetics; Plant Proteins - genetics; Plant Proteins - isolation & purification; Plant Proteins - metabolism; Plant Roots - chemistry; Plant Roots - genetics; Proteins; roots; seeds; Seeds - chemistry; Seeds - genetics; Sequence Analysis, Protein; Sequence Homology, Amino Acid; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; stability; Tissue Distribution; Zea mays; Zea mays - chemistry; Zea mays - genetics; Zea mays - metabolism
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1023/A:1006311121717

The nuclear HMG1 proteins of higher plants are small non-histone proteins that have DNA-bending activity and are considered architectural factors in chromatin. The occurrence of the chromosomal HMG1 proteins, HMGa, HMGc1/2 and HMGd, in various maize tissues was analyzed, and in the course of these studies a novel HMG1 protein, now termed HMGe, was identified. Purification and characterization of HMGe (M(r) 13 655) and cloning of the corresponding cDNA revealed that it displays only moderate similarity to other members of the plant HMG1 protein family. The five maize HMG1 proteins could be detected in kernels, leaves, roots and suspension culture cells, indicating that these proteins can be expressed simultaneously and occur relatively ubiquitously. However, the various HMG1 proteins are present in significantly different quantities with HMGa and HMGc1/2 being the most abundant HMG1 proteins in all tissues tested. Furthermore, the relative amounts of the various HMG1 proteins differ among the tissues examined. The HMG1 proteins were found to be relatively stable proteins in vivo, with HMGc1/2, HMGd and HMGe having a half-life of ca. 50 h in cultured cells, while the half-life of the HMGa protein is ca. 65 h. Collectively, these findings are compatible with the concept that the different plant HMG1 proteins might act as general architectural proteins in concert with site-specific factors in the assembly of certain nucleoprotein structures involved in various biological processes.