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bioRxiv · 10.1101/2020.05.19.103069

Improved reference genome for Cyclotella cryptica CCMP332, a model for cell wall morphogenesis, salinity adaptation, and lipid production in diatoms (Bacillariophyta)

Roberts, W. R.·Downey, K. M.·Ruck, E. C.·Traller, J. C.·Alverson, A. J.
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Abstract

The diatom, Cyclotella cryptica, is a well-established experimental model for physiological studies and, more recently, biotechnology applications of diatoms. To further facilitate its use as a model diatom species, we report an improved reference genome assembly and annotation for C. cryptica strain CCMP332. We used a combination of long- and short-read sequencing to assemble a high-quality and contaminant-free genome. The genome is 171 Mb in size and consists of 662 scaffolds with a scaffold N50 of 494 kb. This represents a 176-fold decrease in scaffold number and 41-fold increase in scaffold N50 compared to the previous assembly. The genome contains 21,250 predicted genes, 75% of which were assigned putative functions. Repetitive DNA comprises 59% of the genome, and an improved classification of repetitive elements indicated that a historically steady accumulation of transposable elements has contributed to the relatively large size of the C. cryptica genome. The high-quality C. cryptica genome will serve as a valuable reference for ecological, genetic, and biotechnology studies of diatoms. Data available fromNCBI BioProjects PRJNA628076 and PRJNA589195

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Roberts, W. R., Downey, K. M., Ruck, E. C., Traller, J. C., Alverson, A. J.. 2020-05-19. Improved reference genome for Cyclotella cryptica CCMP332, a model for cell wall morphogenesis, salinity adaptation, and lipid production in diatoms (Bacillariophyta). https://doi.org/10.1101/2020.05.19.103069

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