Water temperature at oviposition sites of Rana luteiventris in northeastern Oregon

Water temperature at which Columbia spotted frog ( Rana luteiventris ) eggs were deposited and developed was determined at 18 oviposition sites in northeastern Oregon in 2000. Mean daily water temperature on the day of initial egg deposition ranged from 7.6° C to 16.0° C with a mean of 9.6 ° C. Maximum water temperatures on the 1st day of egg deposition ranged from 9.8° C to 20.2° C and averaged 15.5° C. Eggs were not deposited on days when maximum water temperature was below 9.4° C. Duration of egg deposition ranged from 1 to 20 days at the 18 sites. Embryos hatched after 12 21 days. Mean and maximum daily water temperatures were significantly correlated with number of days to hatching. Key words: Columbia spotted frog, embryonic temperature tolerance, northeastern Oregon, Rana luteiventris, ranid.     

Complex inheritance of familial hypercholanemia with associated mutations in TJP2 and BAAT

Familial hypercholanemia (FHC) is characterized by elevated serum bile acid concentrations, itching, and fat malabsorption. We show here that FHC in Amish individuals is associated with mutations in tight junction protein 2 (encoded by TJP2, also known as ZO-2) and bile acid Coenzyme A: amino acid N-acyltransferase (encoded by BAAT). The mutation of TJP2, which occurs in the first PDZ domain, reduces domain stability and ligand binding in vitro. We noted a morphological change in hepatic tight junctions. The mutation of BAAT, a bile acid-conjugating enzyme, abrogates enzyme activity; serum of individuals homozygous with respect to this mutation contains only unconjugated bile acids. Mutations in both TJP2 and BAAT may disrupt bile acid transport and circulation. Inheritance seems to be oligogenic, with genotype at BAAT modifying penetrance in individuals homozygous with respect to the mutation in TJP2.     

An attractant pheromone with common properties in three reptile ticks

Summary Female reptile ticks produce a pheromone which attracts conspecific, and less strongly, non-conspecific males over short distances.