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{{Taxobox
{{Taxobox
| color = aqua
| color = aqua
| name = ''Noctiluca scintillans''
| name = ''Noctiluca scintillans''
| image = Noctiluca scintillans varias.jpg
| status =
| domain = Eukaryota
| image = Noctiluca.jpg
| phylum = Dinoflagellata
| domain = [[Eukaryota]]
| class = Noctiluciphyceae
| Kingdom = [[Chromalveolata]]
| order = Noctilucales
| Phylum = [[Dinoflagellata]]
| family = Noctilucaceae
| Class = [[Noctiluciphyceae]]
| genus = Noctiluca
| Order = [[Noctilucales]]
| species = ''N.scintillans''
| Family = [[Noctilucaceae]]
| binomial name = ''Noctiluca scintillans''
| genus = ''[[Noctiluca]]''
| binomial_authority =
| species = '''''N. scintillans'''''
| binomial = ''Noctiluca scintillans''
| binomial_authority =
}}
}}
==Description and Significance==
==Description and Significance==
 
''Noctiluca scintillans'', also known as the sea sparkle, is a single-celled dinoflagellate that exhibits bioluminescence. They are free-living marine plankton, which range between 200-2000 micrometers <ref name=dic /> in diameter. They are found mostly in estuaries and other coastal regions and can be found in both warm and cold waters. ''N. scintillans'' are heterotrophic and non-photosynthetic, meaning they receive their carbon from organic compounds and receive their energy through the ingestion of organic substances. They don’t have any chloroplasts so, their cytoplasm is relatively clear. ''N. scintillans'' are non-motile, even though they possess a flagellum, and only move vertically by changing their buoyancy using gas vacuoles.<ref>{{cite web
 
  | last = Asare
''Noctiluca scintillans'', also known as sea sparkles, are single-celled dinoflagellates that exhibit bioluminescence. They are free-living marine plankton, which range between 200-2000 micrometers in diameter. They are found mostly in estuaries and other coastal regions and can be found in both warm and cold waters. ''N. scintillans'' are heterotrophic and non-photosynthetic, meaning they receive their carbon from organic compounds and receive their energy through the ingestion of organic substances. They don’t have any chloroplasts so, their cytoplasm is relatively clear. ''Noctiluca scintillans'' are non-motile, even though they possess a flagellum, and only move vertically by changing their buoyancy using gas vacuoles. ''N. scintillans'' can reproduce asexually, by binary fission, and sexually, using isogametes through a diplontic lifecycle.
  | first = Amma
  | title = Bioluminescence
  | url=http://www.milton.edu/academics/pages/marinebio/biolum.html
  | accessdate = 2009-04}}
</ref> N. scintillans can reproduce asexually, by binary fission, and sexually, using isogametes through a diplontic lifecycle.
<ref name=harmful>{{cite web
  | last = Macartney
  | first = N/A
  | title = Identifying Harmful Marine Dinoflagellates
  | url= http://botany.si.edu/references/dinoflag/Taxa/Nscintillans.htm
  | accessdate = 2009-04 }} </ref>


The bioluminescent property of ''N. scintillans'' is a tourist attraction for many countries throughout the world. People would take boat rides and watch these dinoflagellates emit flashes of blue light when disturbed, giving them the name sea sparkle.
The bioluminescent property of ''N. scintillans'' is a tourist attraction for many countries throughout the world. People would take boat rides and watch these dinoflagellates emit flashes of blue light when disturbed, giving them the name sea sparkle.


==Genome and Structure==
==Genome and Structure==
Many studies have been done on the luciferase gene within the scintillons of ''N. scintillans''. They have found that ''N. scintillans'' is genetically distinct from the other six bioluminescent dinoflagellates that have been studied, because the N-terminus is missing a ~100aa sequence. Still the N-terminus is closely related to the other bioluminescent dinoflagellates. The C-terminal end of this gene, however, is closely related to a separate gene in a photosynthetic dinoflagellate. It is as if these two genes in the photosynthetic species were fused in ''N. scintillans''. Studies of the 18S ribosomal DNA of ''N. scintillans'', also suggested that they were one of the first bioluminescent species to branch off because their genomic sequence is most closely related to the ancestral gene.<ref>{{cite journal
  | authorlink = Liyun Liu
  | title = Two Different Domains of the Luciferase Gene in the Heterotrophic Dinoflagellate Noctiluca Scintillans Occur as Two Separate Genes in Photosynthetic Species
  | journal = PNAS
  | volume = 104.3
  | pages = 696-701
  | date = 2007}} </ref>


The entire genome for ''Noctiluca scintillans'' has not been sequenced. However many studies have been done on the luciferase gene within the scintillons of this species. They have found that ''Noctiluca scintillans'' is genetically distinct from the other six bioluminescent dinoflagellates that have been studied, because the N-terminal is missing a ~100aa sequence. Still the N-terminal is closely related to the other bioluminescent dinoflagellates.  The C-terminal of this gene, however, is closely related to a separate gene in a photosynthetic dinoflagellate. It is as if these two genes in the photosynthetic species were fused in ''N. scintillans''.  Studies of the 18S ribosomal DNA of ''N. scintillans'', also suggested that they were one of the first species to branch off because their genomic sequence is most closely related to the ancestral gene.
==Bioluminescence==
[[Image:Bioluminescence.jpg|right|200 px]]
 
''N. scintillans'' may use bioluminescence for many different purposes. It could be used as a defense against predators, an offensive strategy to keep away other predators from their prey, or as a means of communication. They emit light, on a circadian rhythm and when they are disturbed, as a flash of bright blue light for no more than a second. Luciferin, an open-chain tetrapyrrole in dinoflagellates that is thought to be derived from chlorophyll, becomes oxidized by molecular oxygen, with the help of the catalyst luciferase, to produce an inactive oxyluciferin and light. This process is called chemiluminescence because it is the convergence of chemical energy into light energy and it occurs within small cytoplasmic bodies called scintillons, where both luciferin and luciferase are stored. Bioluminescence is triggered by a drop of pH within the cytoplasm. <ref>{{cite web
  | last = Hastings
  | first = J.W.
  | title = Bioluminescence
  | url=http://mips.stanford.edu/public/abstracts/hastings.pdf
  | accessdate = 2009-04 }}  </ref>


==Cell Structure and Metabolism==
==Cell Structure and Metabolism==
''N. scintillans'' has a round, balloon-like, body shape and is unarmored, meaning it does not have a protective shell. Since they do not photosynthesize they do not contain chloroplasts, and thus are fairly clear. The red and green color usually associated with this species during red and green tides, are due to the pigments of the photosynthetic symbionts within the vacuoles of ''N. scintillans'' and not the species itself. ''N. scintillans'' has a ventral groove that runs through it's body which contains the flagellum, a tooth and a tentacle. <ref name=harmful />They also have a mouth-like structure called the cytostome, which is used to capture and consume prey. Their nucleus contains chromosomes that are always condensed (dinokaryotic), except during interphase. <ref name=dino> {{cite web
  | last = Hoppenrath
  | first = Mona
  | title = Dinoflagellates
  | url=http://tolweb.org/Dinoflagellates/2445
  | accessdate = 2009-04 }} </ref>


''Noctiluca scintillans'' has a round, balloon-like, body shape and is unarmored, meaning it does not have a protective shell. Since they do not photosynthesize, they don’t have chloroplasts and thus are fairly clear. The red and green color usually associated with this species, in the red and green tides, are due to the pigments of the photosynthetic symbionts within the vacuoles of ''N. scintillans'' and not the species itself. ''N. scintillans'' have a ventral groove that run through their bodies which contains the flagellum, a tooth and a tentacle. They also have a mouth-like structure called the cytostome which they use to capture and consume prey.
''N. scintillans'' is a phagotrophic species with many food vacuoles found throughout it's cytoplasm. They engulf smaller marine species such as diatoms, protozoans, fish eggs, and certain bacteria, and then digest them in these food vacuoles.<ref name=dic>{{cite web
 
  | last = N/A
''Noctiluca scintillans'' is a phagotrophic species with many food vacuoles found throughout their cytoplasm. They engulf smaller marine species such as diatoms, protozoans, fish eggs, and certain bacteria and then digest them in these food vacuoles. ''N. scintillans'' also contain gas vacuoles, which are filled with ammonia gas, that allow them to control their buoyancy.
  | first = N/A
 
  | title = Noctiluca Scintillans
Small cytoplasmic bodies within the cells, called scintillons, are what give ''N. scintillans'' their bioluminescent property. Luciferase and luciferin are both found in those structures and it is the interaction of both these molecules that emits light.
  | url=http://eol.org/pages/901153/hierarchy_entries/45732435/details
  | accessdate = 2009-04 }}</ref> ''N. scintillans'' also contains gas vacuoles, which are filled with ammonia gas, that allow them to control their buoyancy. <ref name=Oman> {{cite journal
  | authorlink = Al-Azri, Adnan
  | title = Seasonality of the Bloom-Forming Hetertrophic dinoflagellate Noctiluca Scintillans in the Gulf of Oman in Relation to Environmental Conditions
  | journal = International Journal of Oceans and Oceanography
  | volume = 2.1
  | pages = 51-60
  | date = 2007}}</ref>


==Ecology and Pathology==
==Ecology and Pathology==
''N. scintillans'' are found mostly in coastal areas, in both temperate and tropical waters. Their population density has been found to be dependent on food availability, which is why they tend to stay in shallow, coastal areas, where phytoplankton thrive. They are also a major factor on the population density of zooplankton. <ref name=zooplankton>
{{cite journal
  | authorlink = Noyan Yilmaz
  | title = Evidences for influence of a heterotrophic dinoflagellate (Noctiluca scintillans) on zooplankton community structure in a highly stratified basin
  | journal = Estuarine, Coastal, and Shelf Science
  | volume = 64.2-3
  | pages = 475-485
  | date = 2005}} </ref>


''Noctiluca scintillans'' are found mostly in coastal areas, in both temperate and tropical waters. Their population density has been found to be dependent on food availability, which is why they tend to stay in shallow, coastal areas, where phytoplankton thrive. They are also a major factor on the population density of zooplankton. 
''N. scintillans'' are sometimes known to have a large population blooms known as red or green tides (depending on what color endosymbionts are present in their vacuoles.) These tides cause the death of many marine animals. ''N. scintillans'' does not, however, release exotoxins like many other dinoflagellates do. Instead, it is believed that they kill these animals by suffocation due to the release of ammonia and carbon dioxide, causing anoxic water conditions. <ref name=dic />
 
''Noctiluca scintillans'' are sometimes known to have a large population boom known as red or green tides (depending on what color endosymbionts are present in their vacuoles.) These tides cause the death of many marine animals. ''N. scintillans'' does not, however, release exotoxins like many other dinoflagellates do. Instead, it is believed that they kill these animals by suffocation due to the release of ammonia and carbon dioxide, causing anoxic water conditions.
 
==Bioluminescence==
 
Noctiluca scintillans may use bioluminescence for many different purposes.  It could be used as a defense against predators, an offensive strategy to keep away other predators from their prey, or as a means of communication.  Usually when they are disturbed, they flash a bright blue light for no more than a second.  Light is emitted when luciferin becomes oxidized by molecular oxygen, with the help of the catalyst luciferase.  This process is called chemiluminescence because it is the convergence of chemical energy into light energy and it occurs inside the scintillons.


==Current Research==
==Current Research==


===Ride Tide of Noctiluca Scintillans and it's Impact on the Coastal Water Quality of the Near-Shore
===Ride Tide of ''Noctiluca Scintillans'' and it's Impact on the Coastal Water Quality of the Near-Shore Waters, Off the Rushikulya River, Bay of Bengal===
Waters, Off the Rushikulya River, Bay of Bengal===
This study is being conducted to check the quality of the water after red tides of ''N. scintillans''. The researchers take samples of the water from different depths and determine the quality of the water by checking temperature, salinity, nitrate, nitrite and phosphate concentration. They found drops in water temperature during bloom periods, as well as a decrease of dissolved oxygen during blooms.  Phosphate, nitrate and silicate levels increased during bloom periods while nitrite levels decreased.  However, they found no correlation between the salinity content of the water and the formations of red tides.<ref>{{cite journal
 
  | authorlink = N/A
This study is being conducted to check the water quality of the water after red tides of N. scintillans. They would take samples of the water from different depths and determine the quality of the water by checking temperature, salinity, nitrate, nitrite and phosphate concentration.
  | title = Ride Tide of Noctiluca Scintillans and it's Impact on the Coastal Water Quality of the Near-Shore Waters, Off the Rushikulya River, Bay of Bengal
 
  | journal = Current Science
===Seasonality of the Bloom-Forming Hetertrophic dinoflagellate Noctiluca Scintillans
  | volume = 93.5
in the Gulf of Oman in Relation to Environmental Conditions===
  | pages = 616-617
  | date = 2007}} </ref>


This study is being conducted to find what environmental factors contribute to the population blooms of Noctiluca Scintillans. They are checking hydrographic, biological factors as well as other factors such as wind intensity.
===Seasonality of the Bloom-Forming Hetertrophic dinoflagellate ''Noctiluca Scintillans'' in the Gulf of Oman in Relation to Environmental Conditions===
This study is being conducted to find what environmental factors contribute to the population blooms of ''Noctiluca scintillans''. They are checking hydrographic and biological factors as well as other factors such as wind intensity. The optimum temperature for the growth of ''N. scintillans'' was between 10-28<sup>o</sup>C and the optimum salinity was between 28-36%.<ref name=Oman />


==References==
==References==
{{reflist}}[[Category:Suggestion Bot Tag]]
Noctiluca : Sparkle of the sea.  1995. Microscopy-UK.  April 2009. http://www.microscopy-
uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/art98/nocti.html
Identifying Harmful Marine Dinoflagellates.  Smithsonian National Museum of Natural History Botany
Department.  April 2009. http://botany.si.edu/references/dinoflag/Taxa/Nscintillans.htm
Nakamura, Yasuro.  "Biomass, feeding and production of Noctiluca scintillans in the Seto Inland Sea,
Japan."  Journal of Plankton Research.  20.11 (1998): 2213-2222
Noyan Yilmaz, Erdoğan Okus¸ and Ahsen Yüksek.  "Evidences for influence of a heterotrophic
dinoflagellate (Noctiluca scintillans) on zooplankton community structure in a highly stratified
basin."  Estuarine, Coastal, and Shelf Science. 64.2-3 (2005): 475-485
"Ride Tide of Noctiluca Scintillans and it's Impact on the Coastal Water Quality of the Near-Shore
Waters, Off the Rushikulya River, Bay of Bengal."  Current Science. 93.5 (2007): 616-617
Al-Azri, Adnan. "Seasonality of the Bloom-Forming Hetertrophic dinoflagellate Noctiluca Scintillans
in the Gulf of Oman in Relation to Environmental Conditions."  International Journal of Oceans and
Oceanography. 2.1 (2007): 51-60
Liu, Liyun.  "Two Different Domains of the Luciferase Gene in the Heterotrophic Dinoflagellate
Noctiluca Scintillans Occur as Two Separate Genes in Photosynthetic Species." PNAS.  104.3 (2007):
696-701
Hoppenrath, Mona and Juan F. Saldarriaga. 2008. Dinoflagellates. Version 16 September 2008 (under
construction). http://tolweb.org/Dinoflagellates/2445/2008.09.16 in The Tree of Life Web Project,
http://tolweb.org/
Asare, Amma.  Bioluminescence.  Milton Academics Marine Biology Department.
http://www.milton.edu/academics/pages/marinebio/biolum.html

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Noctiluca scintillans
Noctiluca.jpg
Scientific classification
Domain: Eukaryota
Genus: Noctiluca
Species: N. scintillans
Binomial name
Noctiluca scintillans

Description and Significance

Noctiluca scintillans, also known as the sea sparkle, is a single-celled dinoflagellate that exhibits bioluminescence. They are free-living marine plankton, which range between 200-2000 micrometers [1] in diameter. They are found mostly in estuaries and other coastal regions and can be found in both warm and cold waters. N. scintillans are heterotrophic and non-photosynthetic, meaning they receive their carbon from organic compounds and receive their energy through the ingestion of organic substances. They don’t have any chloroplasts so, their cytoplasm is relatively clear. N. scintillans are non-motile, even though they possess a flagellum, and only move vertically by changing their buoyancy using gas vacuoles.[2] N. scintillans can reproduce asexually, by binary fission, and sexually, using isogametes through a diplontic lifecycle. [3]

The bioluminescent property of N. scintillans is a tourist attraction for many countries throughout the world. People would take boat rides and watch these dinoflagellates emit flashes of blue light when disturbed, giving them the name sea sparkle.

Genome and Structure

Many studies have been done on the luciferase gene within the scintillons of N. scintillans. They have found that N. scintillans is genetically distinct from the other six bioluminescent dinoflagellates that have been studied, because the N-terminus is missing a ~100aa sequence. Still the N-terminus is closely related to the other bioluminescent dinoflagellates. The C-terminal end of this gene, however, is closely related to a separate gene in a photosynthetic dinoflagellate. It is as if these two genes in the photosynthetic species were fused in N. scintillans. Studies of the 18S ribosomal DNA of N. scintillans, also suggested that they were one of the first bioluminescent species to branch off because their genomic sequence is most closely related to the ancestral gene.[4]

Bioluminescence

Bioluminescence.jpg

N. scintillans may use bioluminescence for many different purposes. It could be used as a defense against predators, an offensive strategy to keep away other predators from their prey, or as a means of communication. They emit light, on a circadian rhythm and when they are disturbed, as a flash of bright blue light for no more than a second. Luciferin, an open-chain tetrapyrrole in dinoflagellates that is thought to be derived from chlorophyll, becomes oxidized by molecular oxygen, with the help of the catalyst luciferase, to produce an inactive oxyluciferin and light. This process is called chemiluminescence because it is the convergence of chemical energy into light energy and it occurs within small cytoplasmic bodies called scintillons, where both luciferin and luciferase are stored. Bioluminescence is triggered by a drop of pH within the cytoplasm. [5]

Cell Structure and Metabolism

N. scintillans has a round, balloon-like, body shape and is unarmored, meaning it does not have a protective shell. Since they do not photosynthesize they do not contain chloroplasts, and thus are fairly clear. The red and green color usually associated with this species during red and green tides, are due to the pigments of the photosynthetic symbionts within the vacuoles of N. scintillans and not the species itself. N. scintillans has a ventral groove that runs through it's body which contains the flagellum, a tooth and a tentacle. [3]They also have a mouth-like structure called the cytostome, which is used to capture and consume prey. Their nucleus contains chromosomes that are always condensed (dinokaryotic), except during interphase. [6]

N. scintillans is a phagotrophic species with many food vacuoles found throughout it's cytoplasm. They engulf smaller marine species such as diatoms, protozoans, fish eggs, and certain bacteria, and then digest them in these food vacuoles.[1] N. scintillans also contains gas vacuoles, which are filled with ammonia gas, that allow them to control their buoyancy. [7]

Ecology and Pathology

N. scintillans are found mostly in coastal areas, in both temperate and tropical waters. Their population density has been found to be dependent on food availability, which is why they tend to stay in shallow, coastal areas, where phytoplankton thrive. They are also a major factor on the population density of zooplankton. [8]

N. scintillans are sometimes known to have a large population blooms known as red or green tides (depending on what color endosymbionts are present in their vacuoles.) These tides cause the death of many marine animals. N. scintillans does not, however, release exotoxins like many other dinoflagellates do. Instead, it is believed that they kill these animals by suffocation due to the release of ammonia and carbon dioxide, causing anoxic water conditions. [1]

Current Research

Ride Tide of Noctiluca Scintillans and it's Impact on the Coastal Water Quality of the Near-Shore Waters, Off the Rushikulya River, Bay of Bengal

This study is being conducted to check the quality of the water after red tides of N. scintillans. The researchers take samples of the water from different depths and determine the quality of the water by checking temperature, salinity, nitrate, nitrite and phosphate concentration. They found drops in water temperature during bloom periods, as well as a decrease of dissolved oxygen during blooms. Phosphate, nitrate and silicate levels increased during bloom periods while nitrite levels decreased. However, they found no correlation between the salinity content of the water and the formations of red tides.[9]

Seasonality of the Bloom-Forming Hetertrophic dinoflagellate Noctiluca Scintillans in the Gulf of Oman in Relation to Environmental Conditions

This study is being conducted to find what environmental factors contribute to the population blooms of Noctiluca scintillans. They are checking hydrographic and biological factors as well as other factors such as wind intensity. The optimum temperature for the growth of N. scintillans was between 10-28oC and the optimum salinity was between 28-36%.[7]

References

  1. 1.0 1.1 1.2 N/A, N/A. Noctiluca Scintillans. Retrieved on 2009-04.
  2. Asare, Amma. Bioluminescence. Retrieved on 2009-04.
  3. 3.0 3.1 Macartney, N/A. Identifying Harmful Marine Dinoflagellates. Retrieved on 2009-04.
  4. (2007) "Two Different Domains of the Luciferase Gene in the Heterotrophic Dinoflagellate Noctiluca Scintillans Occur as Two Separate Genes in Photosynthetic Species". PNAS 104.3: 696-701.
  5. Hastings, J.W.. Bioluminescence. Retrieved on 2009-04.
  6. Hoppenrath, Mona. Dinoflagellates. Retrieved on 2009-04.
  7. 7.0 7.1 (2007) "Seasonality of the Bloom-Forming Hetertrophic dinoflagellate Noctiluca Scintillans in the Gulf of Oman in Relation to Environmental Conditions". International Journal of Oceans and Oceanography 2.1: 51-60.
  8. (2005) "Evidences for influence of a heterotrophic dinoflagellate (Noctiluca scintillans) on zooplankton community structure in a highly stratified basin". Estuarine, Coastal, and Shelf Science 64.2-3: 475-485.
  9. (2007) "Ride Tide of Noctiluca Scintillans and it's Impact on the Coastal Water Quality of the Near-Shore Waters, Off the Rushikulya River, Bay of Bengal". Current Science 93.5: 616-617.