A New Angle Around OTX015 Just Launched

Two types of carbamoyl phosphate synthase (CPS) genes were present in the combined transcriptome, previously designated in diatoms as unCPS and pgCPS (Allen et al., 2011). The former is localized to the mitochondria and is involved in the urea cycle, using ammonium as a substrate, while the latter is likely cytosolic and uses glutamine as a substrate in the first committed step of pyrimidine synthesis (Allen et al., 2011). There were six copies of pgCPS in the transcriptome, three of which were not differentially expressed in any of the treatments. The other three were not differentially expressed under N-limitation but had relatively lower expression under P-limitation (Figure ?(Figure3A).3A). Both unCPS genes found in the transcriptomes had lower transcription levels in the P-limited treatment, but neither were differentially expressed under N-limitation. Two other genes involved in the urea cycle, argininosuccinate synthase and argininosuccinate lyase, also had higher expression levels under N-limitation (Table ?(Table3).3). Under P-limitation, argininosuccinate synthase was not differentially expressed while argininosuccinate lyase had a slightly lower expression level compared to the replete treatment (Table ?(Table3).3). The other urea cycle genes, arginine, and ornithine transcarbamoyltransferase were not differentially expressed among the three treatments. Phosphate transporters Overall, expression levels of phosphate transporters were higher in the P-limited treatment, but were not statistically different in the N-limited treatment, compared to the replete treatment (Figure ?(Figure3E).3E). The most highly expressed gene in the P-limited treatment was one of two genes that were annotated as putative pho4 family genes, a high-affinity sodium-phosphate transporter family that is generally regulated by phosphorous starvation in fungi (Dick et al., 2014) (Supplemental Figure 2). The expression level of this gene was higher in the P-limited treatment compared to the replete treatment. The second pho4 gene was not differentially expressed. Three other putative sodium-dependent inorganic phosphate transporters most related to the Solute Carrier family (SLC) were more highly expressed in the P-limited Selleck OTX015 condition, while another one annotated as a sodium-dependent inorganic phosphate transporter of the Major Facilitator Superfamily (MFS) was not differentially expressed. Photosynthesis proteins Photosynthesis-related proteins found in the P. parvum transcriptome consisted of chlorophyll A-B binding proteins and light-harvesting proteins. Most photosynthesis-related genes are encoded in the chloroplast genome, and thus were not recovered in our datasets due to the poly-A+ enrichment technique used. We found 38 chlorophyll A-B binding protein genes that were differentially expressed among the treatments. Most of these genes had lowest expression levels in the N-limited treatment (Figure ?(Figure4A).4A).