The green sturgeon, Acipenser medirostris, is one of two acipenserid fishes native to the temperate waters of the Pacific coast of North America. Originally, three species of sturgeon were described from this region, and this one named ‘‘medirostris’’ or ‘‘middle snout’’ based on the length of its rostrum relative to the other purported species (Ayers 1854), both of which were later determined ...

Here we present the first isolation of major histocompatibility complex (MHC) class I genes from two ancient fish, paddlefish (Polyodon spathula) and Chinese sturgeon (Acipenser sinensis). Seventeen sequences obtained showed high polymorphism and positive natural selection with dN/dS>1. Evolutionary relationships revealed that sequences from paddlefish and Chinese sturgeon distinguished from ot...

A multistressor study was conducted to investigate interactive effects of nutritional status and salinity on osmoregulation of juvenile white sturgeon. Our hypothesis was that lower nutritional status would decrease the salinity tolerance of juvenile white sturgeon. A four-week feed restriction (12.5%, 25%, 50%, 100% of optimum feeding rate: OFR defined as the rate (% body weight per day) at wh...

Osteocalcin (OC) and matrix Gla protein (MGP) are considered evolutionarily related because they share key structural features, although they have been described to exert different functions. In this work, we report the identification and characterization of both OC and MGP from the Adriatic sturgeon, a ray-finned fish characterized by a slow evolution and the retention of many ancestral featur...

Data from 1238 fishes from 19 sturgeon species and 1 paddlefish were used to analyze heteroplasmy in sturgeon. Lengths of central repeat units ranged from 74 to 83 bp among sturgeon species. No repeat sequence was found in the paddlefish, Polyodon spathula. A general feature of the repeat units was the presence of termination associated sequence (TAS) motifs. About 50% of 138 interspecific muta...

The solubility of protein components in salmon (Oncorhynchus keta) and sturgeon (Acipenser transmontanus) caviar in distilled water, 5% (w/v) NaCl, 70% (v/v) ethanol at 65C, and 0.2% (w/v) NaOH was determined. The salt soluble proteins were the predominant fraction and constituted 84.2% of the recovered protein in salmon and 86.1% in sturgeon samples. The two most prominent protein fractions (1...

The Sox9 gene of Acipenser sturio, one of the most primitive vertebrates, was analyzed. No sex-specific differences were observed. Sturgeon Sox9 consists of three exons and two introns with completely conserved exon-intron boundaries showing high levels of homology to other vertebrate Sox9 sequences, especially in the N-terminus region containing the HMG box. We found strong evidence for negati...

Fish skin is essential for survival, maintenance of body shape, and protection against the shock and infection. During week 1 of sturgeon larval development, the epidermis is thin and not differentiated in various layers yet, but by week 4-6 the thickness increases and various layers appear, depending upon the region of the body. Mucous cells differentiate early in development on the surface of...

Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted. Although there is paucity of information, it is critical to test the network of biological responses underlying the capacity of animals to tolerate curre...

Ribosomal DNA in sturgeon is informative when analyzed at the molecular level because it bears unique characteristics that are, to a certain extent, ancestral within vertebrates. In this paper, we examine the structure and the molecular evolution of the 5S ribosomal DNA (rDNA) region in 13 sturgeon species, comparing both the 5S ribosomal RNA (rRNA) genes and the non-transcribed spacer (NTS) se...