Dynamics of the Striped Bass (Morone saxatilis) Ovary Proteome Reveal a Complex Network of the Translasome

Abstract

We evaluated changes in the striped bass (Morone saxatilis) ovary proteome during the annual reproductive cycle using label-free quantitative mass spectrometry and a novel machine learning analysis based on K-means clustering and support vector machines. Modulated modularity clustering was used to group co-variable proteins into expression modules and Gene Ontology (GO) biological process and KEGG pathway enrichment analyses were conducted for proteins within those modules. We discovered that components of the ribosome along with translation initiation and elongation factors generally decrease as the annual ovarian cycle progresses toward ovulation, concomitant with a slight increase in components of the 26S-proteasome. Co-variation within more than one expression module of components from these two multi-protein complexes suggests that they are not only co-regulated, but that co-regulation occurs through more than one sub-network. These components also co-vary with subunits of the TCP-1 chaperonin system and enzymes of intermediary metabolic pathways, suggesting that protein folding and cellular bioenergetic state play important roles in protein synthesis and degradation. We provide further evidence to suggest that protein synthesis and degradation are intimately linked, and our results support function of a proteasome-ribosome supercomplex known as the translasome.

Lrp13 is a novel vertebrate lipoprotein receptor that binds vitellogenins in teleost fishes

“…NanoLC-MS/MS data for all proteins are reported in Reading et al ( 24 ). The Lrp13 in the ovary during LVG and PVG was elevated compared with ESG ( P < 0.0402) ( Fig.…”

“…Aliquots of solubilized ovary membrane proteins, affi nity purifi ed Vtgrs, and purifi ed VtgAa/b were processed for LC-ESI-MS/MS using an LTQ linear ion trap mass spectrometer (Thermo, San Jose, CA) at the NCSU Genomic Sciences Laboratory (Raleigh, NC). Samples were analyzed in quadruplicate and ion fragmentation spectra were queried by MASCOT (Matrix Science, Boston, MA) against white perch VtgAa, VtgAb, VtgC ( 16 ), white perch Lr8 Ϫ ( 18 ), and the translated striped bass ovary transcriptome ( 24,25 ).…”

“…Ovary tissues from striped bass (n = 3) were collected by dissection or biopsy using a plastic cannula inserted through the urogenital pore at four time points: August (weight 1.90 ± 0.61 kg; total length 512 ± 18.0 mm), November (3.80 ± 0.14 kg; 625 ± 6.0 mm), February (4.40 ± 0.94 kg; 626 ± 46.6 mm), and April (4.54 ± 1.37 kg; 663 ± 74.5 mm). The most advanced oocytes during these time points represented one of four oocyte growth stages ( 24 ): early secondary growth (ESG, oocyte diameter 310 ± 21.8 m), mid-vitellogenic growth (MVG, 503 ± 60.1 m), late-vitellogenic growth (LVG, 831 ± 276 m), and post-vitellogenic growth (PVG, 986 ± 33.0 m), respectively. Ovary and liver samples were preserved in RNALater (Ambion, Austin, TX) for real-time quantitative RT-PCR.…”

“…Striped bass ovary extracts were subjected to reversed phase HPLC and tandem mass spectrometry (nanoLC-MS/MS) using an Eksigent (Dublin, CA) nanoLC-1D+ system with autosampler coupled to a hybrid Thermo Fisher LTQ Orbitrap XL mass spectrometer (Thermo Scientifi c, San Jose, CA), as we previously reported ( 24 ). Spectral counts of the protein encoded by striped bass contig 00618 ( 25 ) (Lrp13) were normalized using ProteoIQ (NuSep, Bogart, GA) and these values were transformed: Log 10 ( y + 1), y = normalized spectral count.…”

Endocrinology: Advances through omics and related technologies

“…Similarly, a transcriptional analysis of fathead minnow ovaries after exposure to a model androgen and antiandrogen identified transcriptional regulators as potential early molecular switches to control phenotypic changes in ovary in response to androgen or antiandrogen exposure (Garcia-Reyero et al, 2009c). Reading et al (2013) used proteomics to examine the ovary in striped bass and found that the proteasome-ribosome supercomplex known as translasome may play an important role of during the ovarian cycle. Flatfish are also of great interest in aquaculture and an oligo-based microarray for the senegalese sole based on multi-tissue library sequencing was developed (Cerdà et al, 2008).…”