Search

Dorsoventral pigment patterning, characterized by a light ventrum and a dark dorsum, is one of the most widespread chromatic adaptations in vertebrate body coloration. In mammals, this countershading depends on differential expression of agouti‐signaling protein (ASIP), which drives a switch of synthesis of one type of melanin to another within melanocytes. Teleost fish share countershading, but the pattern results from a differential distribution of multiple types of chromatophores, with black–brown melanophores most abundant in the dorsal body and reflective iridophores most abundant in the ventral body. We previously showed that Asip1 (a fish ortholog of mammalian ASIP) plays a role in patterning melanophores. This observation leads to the surprising hypothesis that agouti may control an evolutionarily conserved pigment pattern by regulating different mechanisms in mammals and fish. To test this hypothesis, we compared two ray‐finned fishes: the teleost zebrafish and the nonteleost spotted gar (Lepisosteus oculatus). By examining the endogenous pattern of asip1 expression in gar, we demonstrate a dorsoventral‐graded distribution of asip1 expression that is highest ventrally, similar to teleosts. Additionally, in the first reported experiments to generate zebrafish transgenic lines carrying a bacterial artificial chromosome (BAC) from spotted gar, we show that both transgenic zebrafish lines embryos replicate the endogenous asip1 expression pattern in adult zebrafish, showing that BAC transgenes from both species contain all of the regulatory elements required for regular asip1 expression within adult ray‐finned fishes. These experiments provide evidence that the mechanism leading to an environmentally important pigment pattern was likely in place before the origin of teleosts, Grant sponsor: Spanish Economy and Competitiveness Ministry; Grant numbers: AGL2011-23581 and AGL2014-52473R; Grant sponsor: NIH; Grant num-bers: R01 OD011116 (alias R01 RR020833) and R24 OD01119004; Grant sponsor: Alexander von Humboldt Foundation; Grant sponsor: Volkswagen Foundation Initiative Evolutionary Biology; Grant number: I/84 815.

Symbiotic performance of Rhizobium leucaenae CFN 299T and CPAO 29.8 under high temperature in comparison to other microsymbionts of common bean. Plants grown under greenhouse controlled condition, at 28/23 °C and 37/23 °C (day/night) and harvested at early flowering (30 days after seedling emergency). (DOCX 16 kb)

Symbiotic performance of Rhizobium leucaenae CFN 299T and CPAO 29.8 under high temperature in comparison to other microsymbionts of common bean. Plants grown under greenhouse controlled condition, at 28/23 °C and 37/23 °C (day/night) and harvested at early flowering (30 days after seedling emergency). (DOCX 16 kb)

General features of the total sequenced and mapped reads. Reads were mapped using a Bayesian inference using Cufflinks v2.11 software. Worst quality reads were removed by means of Picard Tools (See the Material and Methods section) (PDF 185 kb)

TLC analysis obtained with 14C labeled N-acetylglucosamine of Nod factors produced by rhizobial strains microsymbionts of Phaseolus vulgaris grown under acid (pH 4.0) or alkaline (pH 9.0) stress. Bacteria were induced (+) or not (−) with a flavonoid nod-gene inducer (apigenin, 3.7 μM). Profiles obtained for R. tropici CIAT 899T were identical to those of R. leucaenae CFN 299T. (PPTX 1271 kb)

TLC analysis obtained with 14C labeled N-acetylglucosamine of Nod factors produced by rhizobial strains microsymbionts of Phaseolus vulgaris grown under acid (pH 4.0) or alkaline (pH 9.0) stress. Bacteria were induced (+) or not (−) with a flavonoid nod-gene inducer (apigenin, 3.7 μM). Profiles obtained for R. tropici CIAT 899T were identical to those of R. leucaenae CFN 299T. (PPTX 1271 kb)

Nod Factor structure biosynthesized in control condition (B− medium) by wild type CIAT 899 and derivatives. (DOC 45 kb)

Nod Factor structure biosynthesized in the presence of 300 mM NaCl by wild type CIAT 899 and derivatives. (DOC 81 kb)

Nod Factor structure biosynthesized in the presence of apigenin (3.7 μM) by wild type CIAT 899 and derivatives. (DOC 72 kb)

Sequences of the primers used in the RT-qPCR and sizes of the PCR products obtained. (DOC 37 kb)