Characterization of a Pollen-Specific cDNA Clone from Zea mays and Its Expression

Abstract

A pollen-specific cDNA clone, Zinc13, has been isolated from a cDNA library constructed to poly(A) RNA from mature maize pollen. The cDNA as shown by primer extension analysis is a full-length copy of the mRNA. The cDNA has been sequenced and is 929 nucleotides in length plus a 47-nucleotide poly(A) tail. Putative polyadenylation signals are identifiable in the 3'-nontranslated region. The mRNA codes for a predicted polypeptide containing 170 amino acid residues and with a molecular mass of 18.3 kilodaltons. The hydropathy profile suggests a possible signal sequence on the amino terminus. A comparison of the nucleotide and deduced amino acid sequence with sequences in data banks has not shown homology to known molecules. In situ hybridizations using RNA probes show that the mRNA is located in the cytoplasm of the vegetative cell of the pollen grain and after germination is distributed throughout the pollen tube cytoplasm.

The amino acid sequence of Ole e I, the major allergen from olive tree (Olea europaea) pollen

“…However, it exhibits substantial amino acid identity with the deduced amino acid sequences of the genes LAT52 from tomato [32] and Zmcl3 from corn [33] in the open reading frame nucleotide segments. 36% and 38% identity was found, respectively, for the tomato and corn deduced proteins (Fig.…”

Cotton (Gossypium hirsutum L.) pollen-specific polygalacturonase mRNA: tissue and temporal specificity of its promoter in transgenic tobacco

“…Characterizations of tissuespecific genes, therefore, are important for the study of tissue or organ development. Gene expression in pollen grains, the male gametophytes of the flowering plants, has been studied in a number of plant species including Zea mays [ 1,9], tomato [4,8,17], Oenothera organensis [5] and Tradescantia paludosa [ 15]. We are examining the gene expression in cotton (Gossypium) pollen to identify genes that are critical to microsporogenesis.…”

Expression of Zm13, a pollen specific maize protein, in Escherichia coli reveals IgE‐binding capacity and allergenic potential

“…Zml3 represents a protein which is specifically expressed in mature maize pollen [16,17]. Significant sequence homologies of Zml3 with other pollen or anther specific proteins have been described, but little information is available regarding the possible biological function of Zml3.…”

“…Sera from 72 grass pollen allergic individuals were characterized by positive case history, skin prick test and RAST as described [22]. A rabbit antiserum raised against a synthetic peptide (amino acids 2742: ADDPNLPDYVIQGR) as deduced from the amino acid sequence of Zml3 [16] was prepared by immunizing a rabbit with the KLH coupled peptide using Freund's adjuvant [23]. The antiserum was purified by affinity chromatography with the synthetic peptide coupled to CNBr activated Sepharose-4B [24] and recognizes the natural Zml3 protein (D.A.…”

“…While allergens related to group l, 2 and 5 grass pollen allergens could not be detected in somatic plant tissues, small amounts of Bet vl and Bet v2 homologous proteins were identified in plant derived food (fruits, vegetables and spices) as elicitors of IgE-mediated food intolerance [10][11][12][13][14].Among pollen specific proteins two maize proteins showed significant sequence homologies to pollen allergens from different plant species. Zm58 was shown to be highly homlogous to the Amb al/2 family of ragweed allergens [15] and Zml3 [16,17] displayed sequence similarity with the major allergen of olive pollen, Ole el [18][19][20], and a rye grass allergen (Lolium perenne), Lol pl 1 [21].…”