Generation of a de novo trascriptome assembly from equine lamellar tissue

The equine hoof is a specialized structure in which the distal skeleton is suspended within the capsule by interdigitated structures known as laminae. Inflammation of this tissue, known as laminitis, is a devastating disease that is the second leading cause of both lameness and euthanasia in the horse. Current research on the laminitic transcriptome focuses on the expression of known genes. However, as this tissue is quite unique and equine annotation is largely derived from computational predictions and gene models from other species, there are likely yet uncharacterized transcripts expressed in the laminae that may be involved in the etiology of laminitis. In order to create a novel annotation resource, we performed whole transcriptome sequencing of sagittal lamellar sections from one control and two laminitis affected horses. Assembly of 113 million 100bp reads resulted in around 75,000 transcripts. Of these, 36,000 corresponded to known annotation in NCBI's non-redundant protein database. RT-PCR of 12 selected annotations confirmed structure and expression in lamellar tissue. Transcriptome sequencing represents a powerful tool to expand on equine annotation and identify novel targets for further laminitis research.