Tan X, Titorenko V I, van der Klei I J, Sulter G J, Haima P, Waterham H R, Eyers M, Harder W, Veenhuis M, Cregg J M
Department of Chemistry, Biochemistry, and Molecular Biology, Oregon Graduate Institute of Science and Technology, Portland 97291-1000, USA.
Curr Genet. 1995 Aug;28(3):248-57. doi: 10.1007/BF00309784.
In the methylotrophic yeast Hansenula polymorpha, approximately 25% of all methanol-utilization-defective (Mut-) mutants are affected in genes required for peroxisome biogenesis (PER genes). Previously, we reported that one group of per mutants, termed Pim-, are characterized by the presence of a few small peroxisomes with the bulk of peroxisomal enzymes located in the cytosol. Here, we describe a second major group of per mutants that were observed to be devoid of any peroxisome-like structure (Per-). In each Per- mutant, the peroxisomal methanol-pathway enzymes alcohol oxidase, catalase and dihydroxyacetone synthase were present and active but located in the cytosol. Together, the Pim- and Per- mutant collections involved mutations in 14 different PER genes. Two of the genes, PER5 and PER7, were represented by both dominant-negative and recessive alleles. Diploids resulting from crosses of dominant per strains and wild-type H. polymorpha were Mut- and harbored peroxisomes with abnormal morphology. This is the first report of dominant-negative mutations affecting peroxisome biogenesis.
在甲基营养型酵母多形汉逊酵母中，所有甲醇利用缺陷型（Mut-）突变体中约25%在过氧化物酶体生物发生所需基因（PER基因）方面受到影响。此前，我们报道过一组per突变体，称为Pim-，其特征是存在一些小的过氧化物酶体，大部分过氧化物酶体酶位于细胞质中。在此，我们描述了另一组主要的per突变体，观察发现它们没有任何类似过氧化物酶体的结构（Per-）。在每个Per-突变体中，过氧化物酶体甲醇途径的酶醇氧化酶、过氧化氢酶和二羟基丙酮合酶都存在且有活性，但位于细胞质中。Pim-和Per-突变体集合总共涉及14个不同PER基因的突变。其中两个基因，PER5和PER7，既有显性负性等位基因，也有隐性等位基因。显性per菌株与野生型多形汉逊酵母杂交产生的二倍体是Mut-，并且含有形态异常的过氧化物酶体。这是关于影响过氧化物酶体生物发生的显性负性突变的首次报道。
