Submitted to: Insect Molecular Biology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/1/2004
Publication Date: 6/1/2004
Citation: Chen, M., Fellers, J.P., Stuart, J.J., Reese, J.C., Liu, X. 2004. A group of related cdnas encoding secreted proteins from hessian fly (mayetiola destructor (say)) salivary glands. Insect Molecular Biology. 13(1), 101-108. Interpretive Summary: Fluid-sucking insects including the Hessian fly inject substances through salivary glands into host plants to partially digest food before sucking the juice up, and/or to manipulate host metabolic pathways for the advantage of the insect survival. This paper reports a group of genes isolated from Hessian fly salivary glands. These genes encode proteins with a special sequence called secretion signal. The secretion signal can guide a protein to move out of the salivary glands, a necessary condition in order for a protein to be injected into host plants. Therefore, the proteins encoded by the genes reported in this manuscript are likely injected into host plants by the Hessian fly and could play important roles in Hessian fly development in wheat plants.
Technical Abstract: A group of related cDNA clones has been isolated and characterized from Hessian fly salivary glands. Members in this group appear to encode proteins with a secretion signal peptide at the N-terminal. The mature putative proteins are small, basic proteins with calculated molecular weights that ranged from 8.5 KD to 10KD, and isoelectric points from 9.92 to 10.90. Sequence variation analysis indicated that there was a strong selection for nucleotide mutations that generate amino acid changes within the coding region. Northern blot analysis revealed that these related genes are expressed only in the first instar larvae, a critical stage that determines if the interaction between a specific Hessian fly biotype and a specific wheat cultivar is compatible. Genomic analysis demonstrated that multiple copies of the same or similar genes are clustered within a short region on chromosome 2A, where two avirulence genes are being mapped to. These observations suggest that the proteins encoded by these related genes may play an important role in Hessian fly virulence.