The Role of Epibionts of Bacteria of the Genus Pseudoalteromonas and Cellular Proteasomes in the Adaptive Plasticity of Marine Cold-Water Sponges

There is a current surge of research interest in the potential role of developmental plasticity in adaptation and evolution. Here we make a case that some of this research effort should explore the adaptive significance of heterokairy, a specific type of plasticity that describes environmentally driven, altered timing of development within a species. This emphasis seems warranted given the pervasive occurrence of heterochrony, altered developmental timing between species, in evolution. We briefly review studies investigating heterochrony within an adaptive context across animal taxa, including examples that explore links between heterokairy and heterochrony. We then outline how sequence heterokairy could be included within the research agenda for developmental plasticity. We suggest that the study of heterokairy may be particularly pertinent in (i) determining the importance of non-adaptive plasticity, and (ii) embedding concepts from comparative embryology such as developmental modularity and disassociation within a developmental plasticity framework.

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4-hydroxyphenylpyruvate dioxygenase thermolability is responsible for temperature-dependent melanogenesis inAeromonas salmonicidasubsp.salmonicida

10.1101/324731 ◽

2018 ◽

Author(s):

Yunqian Qiao ◽

Jiao Wang ◽

He Wang ◽

Baozhong Chai ◽

Chufeng Rao ◽

...

Keyword(s):

Cold Water ◽

Biological Significance ◽

Adaptive Strategy ◽

Aeromonas Salmonicida ◽

Temperature Dependent ◽

Ideal Model ◽

Melanin Production ◽

Water Fish ◽

Insight Into

AbstractAeromonas salmonicidasubsp.salmonicida(A.s.s) is a major pathogen affecting fisheries worldwide. It is a well-known member of the pigmentedAeromonasspecies, which produces melanin at ≤ 22 °C. However, melanogenesis decreases as the culture temperature increases and is completely suppressed at 30-35 °C while bacterial growth is not affected. The mechanism and biological significance of this temperature-dependent melanogenesis are not clear. Heterologous expression of anA.s.s.4-hydroxyphenylpyruvate dioxygenase (HppD), the most crucial enzyme in the HGA-melanin synthesis pathway, results in thermosensitive pigmentation inEscherichia coli, suggesting that HppD plays a key role in this process. In the current study, we demonstrated that the extreme thermolability of HppD is responsible for the temperature-dependent melanization ofA.s.s.Substitutions in three residues, Ser18, Pro103, or Leu119 of HppD fromA.s.sincreases the thermolability of this enzyme and results in temperature-independent melanogenesis. Moreover, replacing the corresponding residues of HppD fromAeromonasmedia strain WS, which forms pigment independent of temperature, with those ofA.s.sHppD leads to thermosensitive melanogenesis. Structural analysis suggested that mutations at these sites, especially at position P103, can strengthen the secondary structure of HppD and greatly improve its thermal stability. In addition, we found that HppD sequences of allA.s.sisolates are identical and that two of the three residues are completely conserved withinA.s.sisolates, which clearly distinguishes these from otherAeromonasstrains. We suggest that this property represents an adaptive strategy to the psychrophilic lifestyle ofA.s.s.ImportanceAeromonas salmonicidasubsp.salmonicida(A.s.s) is the causative agent of furunculosis, a bacterial septicemia of cold water fish of theSalmonidaefamily. As it has a well-defined host range,A.s.shas become an ideal model to investigate the co-evolution of host and pathogen. For many pathogens, melanin production is associated with virulence. Although other species ofAeromonascan produce melanin,A.s.sis the only member of this genus that has been reported to exhibit temperature-dependent melanization. Here we demonstrate that thermosensitive melanogenesis inA.s.sstrains is due to the thermolability of 4-hydroxyphenylpyruvate dioxygenase (HppD). The strictly conservedhppDsequences amongA.s.sand the exclusive thermosensitive pigmentation of these strains might provide insight into the role of melanin in the adaptation to a particular host, and offer a novel molecular marker to readily differentiateA.s.sstrains from otherA. salmonicidasubspecies andAeromonasspecies.

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Role of cold water and beta-effect in the formation of the East Korean Warm Current in the East/Japan Sea: a numerical experiment

Ocean Dynamics ◽

10.1007/s10236-018-1175-3 ◽

2018 ◽

Vol 68 (8) ◽

pp. 1013-1023 ◽

Cited By ~ 1

Author(s):

Yong-Yub Kim ◽

Yang-Ki Cho ◽

Young Ho Kim

Keyword(s):

Numerical Experiment ◽

Cold Water ◽

Japan Sea ◽

Warm Current ◽

Beta Effect ◽

East Korean Warm Current

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Abstract 4166: Role of CD44 as a regulator of adaptive plasticity in pancreatic cancer cells

10.1158/1538-7445.am2017-4166 ◽

2017 ◽

Author(s):

Chen Chen ◽

Shujie Zhao ◽

Xiangru Zhao ◽

James W. Freeman

Keyword(s):

Pancreatic Cancer ◽

Cancer Cells ◽

Adaptive Plasticity ◽

Pancreatic Cancer Cells

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The role of allelopathy in legume decline in pastures. III. Tolerance of subterranean clover lines to the allelopathic compounds released from Phalaris residues

Australian Journal of Agricultural Research ◽

10.1071/ar9951039 ◽

1995 ◽

Vol 46 (5) ◽

pp. 1039 ◽

Cited By ~ 5

Author(s):

JH Leigh ◽

DM Halsall ◽

WJ Muller ◽

RN Oram ◽

JP Edlington ◽

...

Keyword(s):

Performance Index ◽

Root Length ◽

Mediterranean Region ◽

Cold Water ◽

Subterranean Clover ◽

Distilled Water ◽

Trifolium Subterraneam ◽

Allelopathic Compounds

The tolerance of 126 lines of subterranean clover (Trifolium subterraneam L.) to allelochemicals released in cold water leachate from dry herbage of phalaris (Phalaris aquatica L. cv. Australian) was examined and compared. The lines were 112 accessions from grassy associations in the Mediterranean region and 14 Australian cultivars. Measures of germination, radicle length, nodulation and root length in seedlings exposed to three concentrations of extract relative to those obtained from seedlings exposed to distilled water only were obtained. A performance index for each line was derived from these measures. Large differences between lines for these four parameters were evident. On the basis of these comparisons, scope exists to select and recommend lines of subclover which are tolerant to these allelochemicals and thus are capable of higher production and greater persistence in long-term perennial phalaris pastures.

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Temperature Is Sufficient to Condition a Flavor Preference for a Cold-Paired Solution in Rats

Chemical Senses ◽

10.1093/chemse/bjaa050 ◽

2020 ◽

Vol 45 (7) ◽

pp. 563-572

Author(s):

Kristen E Kay ◽

Laura E Martin ◽

Kimberly F James ◽

Sashel M Haygood ◽

Ann-Marie Torregrossa

Keyword(s):

Home Cage ◽

Cold Water ◽

Cold Temperature ◽

Warm Water ◽

Flavor Preference ◽

Different Temperatures ◽

Stimulus Temperature ◽

Preference Tests

Abstract Increasing evidence suggests that stimulus temperature modifies taste signaling. However, understanding how temperature modifies taste-driven behavior is difficult to separate as we must first understand how temperature alone modifies behavior. Previous work has suggested that cold water is more rewarding and “satiating” than warm water, and water above orolingual temperature is avoided in brief-access testing. We explored the strength of cold water preference and warm water avoidance by asking: (1) if cold temperature alone was sufficient to condition a flavor preference and (2) if avoidance of warm stimuli is driven by novelty. We addressed these questions using custom-designed equipment that allows us to monitor and maintain solution temperatures. We conducted two-bottle preference tests, after pairing Kool-Aid flavors with 10 or 40 °C. Rats preferred the flavor paired with cold temperature, both while it was cold and for 1 day while solutions were presented at 22 °C. We then examined the role of novelty in avoidance of 40 °C. Rats were maintained on 10, 22, or 40 °C water in their home cage to increase familiarity with the temperatures. Rats were then subject to a series of brief-access taste tests to water or sucrose at 10 to 40 °C. Rats that had 40 °C experience licked more to 40 °C water, but not sucrose, during brief-access testing. In a series of two-bottle preference tests, rats maintained on 40 °C water had a decreased preference for 10 °C water when paired opposite 40 °C water. Together, these data contribute to our understanding of orosensory-driven behavior with water at different temperatures.

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Changes in Foliar Functional Traits of S. pyrenaicus subsp. carpetanus under the Ongoing Climate Change: A Retrospective Survey

Plants ◽

10.3390/plants9030395 ◽

2020 ◽

Vol 9 (3) ◽

pp. 395

Author(s):

Rosina Magaña Ugarte ◽

Adrián Escudero ◽

Daniel Sánchez Mata ◽

Rosario G. Gavilán

Keyword(s):

Stomatal Density ◽

Weather Conditions ◽

Plant Performance ◽

Adaptive Plasticity ◽

Mountain Areas ◽

Stomatal Size ◽

Physiological Approach ◽

Stomatal Traits

The sensitivity of stomatal behavior and patterning (i.e., distribution, density, size) to environmental stimuli, renders them crucial for defining the physiological performance of leaves. Thus, assessing long-term modifications in stomatal traits in conserved specimens arises as a valuable eco-physiological approach to predict how the rising trend of warmer, drier summers could affect plant fitness; particularly in mountain areas already experiencing climate aggravation and lacking the related monitoring schemes like Mediterranean high-mountains. Variations in foliar and stomatal traits were studied in conserved specimens of Senecio pyrenaicus subsp. carpetanus from Sierra de Guadarrama over the past 71 years. Our findings revealed decreasing trends in leaf width, stomatal size, and increasing tendency in stomatal density, all correlated with the recent 30-year climate exacerbation in these mountains. This evidenced a positive selection favoring traits that allow safeguarding plant performance under drier, hotter weather conditions. The significant relation between stomatal traits and climatic variables upholds the role of stomatal patterning in sensing environmental cues in this species, feasibly optimizing physiological responses involved in the growth–water loss trade-off. The transition to smaller, densely packed stomata observed in recent decades could indicate local-adaptive plasticity in this species, enhancing stomatal response, as coarser environmental conditions take place in Sierra de Guadarrama.

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Diversity of the sponge fauna associated with white coral banks from two Sardinian canyons (Mediterranean Sea)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315419000948 ◽

2019 ◽

Vol 99 (8) ◽

pp. 1735-1751 ◽

Cited By ~ 2

Author(s):

M. Bertolino ◽

S. Ricci ◽

S. Canese ◽

A. Cau ◽

G. Bavestrello ◽

...

Keyword(s):

Mediterranean Sea ◽

Cold Water ◽

Three Dimensional ◽

Western Mediterranean ◽

Tyrrhenian Sea ◽

Lophelia Pertusa ◽

Wide Range ◽

Santa Maria

AbstractThe three-dimensional coral scaffolds formed by the skeletons of the cold-water corals Madrepora oculata and Lophelia pertusa represent an important deep-sea hard substratum and create an optimal shelter for a rich associated fauna in which the contribution of Porifera has still not been fully considered. The taxonomic analysis of sponges collected from two Sardinian canyons (Nora and Coda Cavallo, 256–408 m) and associated with the dead coral matrix resulted in 28 species, including new records for the Mediterranean Sea, Italian fauna or Central Tyrrhenian Sea. In addition, for many species this is the first finding associated with the coral framework or the first documentation of the in situ morphology. The taxonomic comparison with sponge assemblages associated with coral frameworks from Santa Maria di Leuca, Strait of Sicily and Bari Canyon, gave the opportunity to evaluate the similarities among geographically separated banks. Overall, the percentage of exclusive species (recorded only in one site), is very high (81%) and only one species is shared by all four sites, suggesting a low connectivity among the sponge communities. The percentage of shared species is higher for the Maltese community, supporting the role of the Sicily Channel as a crossroads between the communities of the eastern and western Mediterranean basins. Here, 55% of the sponges associated to the coral framework are also reported in shallow-water coralligenous assemblages, indicating a high bathymetric connectivity as well as an ecological plasticity allowing these species to occupy a wide range of small, dark refuges.

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