• Title/Summary/Keyword: Biological evolution

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Gregarinidra (Bryozoa: Gymnolaemata: Flustridae) of Korea

  • Hyun Sook Chae;Ho Jin Yang;Bum Sik Min;Ji Eun Seo
    • Animal Systematics, Evolution and Diversity
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    • v.40 no.1
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    • pp.35-41
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    • 2024
  • Two species belonging to the genus Gregarinidra Barroso, 1949 (Bryozoa: Gymnolaemata: Flustridae) were first found in this study from Korean waters. Gregarinidra furcula n. sp. is new to science, and G. incrustans (Silén, 1941) is newly added to the Korean fauna. Species belonging to this genus are primarily distinguished by two characteristics: interzooidal avicularia and marginal spines. The pitchforked spines clearly distinguish G. furcula n. sp. from the other Gregarinidra species, and G. incrustans shows the difference by having blunt spines and short-triangular avicularia. Gregarinidra incrustans was known to be distributed only in Japan until this species was reported from the South Sea, Korea, in the present study. This study provides descriptions of two species with detailed illustrations by scanning electron microscopy, distributional data, and a taxonomic key to the Korean Gregarinidra species. With the addition of two species reported herein, four Korean Gregarinidra are recorded: G. corbula Seo, 1996, G. furcula new species, G. incrustans(Silén, 1941), and G. serrata (MacGillivray, 1869). Finally, Gregarinidra totals 10 species worldwide.

A New Species and a New Record of Escharoides (Bryozoa: Gymnolaemata: Flustridae) in Korea

  • Hyun Sook Chae;Ho Jin Yang;Bum Sik Min;Ji Eun Seo
    • Animal Systematics, Evolution and Diversity
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    • v.40 no.1
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    • pp.42-46
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    • 2024
  • Two species from the genus Escharoides Milne Edwards, 1836, E. biseriatata and E. buffonellarioides n. sp. Were first found in Korean waters in this study. Their colonies were collected from two locations in the South Sea, Korea: Tongyeong Marine Ranch in 2004 and Daebyeon Port in 2009. Escharoides biseriatata shows a difference in the position of avicularia from the Chinese specimens. While avicularia are lateral to the orifice in Chinese specimens, the ones in Korean specimens seem to be located more latero-proximally. Since Escharoides biseriatata was reported as fouling bryozoans in China in 2001, this species first occurred at Daebyeon Port in Korea in this study. Escharoides buffonellarioides n. sp. is similar to E. adeonelloides in morphological features of zooids but is clearly distinguished by having the erect colonial form of small masses. With the addition of two species reported herein, four Korean Escharoides are recorded: E. biseriatata, E. buffonellarioides, E. excavata, and E. sauroglossa.

One New Species and One New Record of Electridae (Bryozoa: Cheilostomatida) from Korea

  • Hyun Sook Chae;Ho Jin Yang;Bum Sik Min;Ji Eun Seo
    • Animal Systematics, Evolution and Diversity
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    • v.40 no.1
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    • pp.73-78
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    • 2024
  • A taxonomic study of the family Electridae Stach, 1937 (Bryozoa: Cheilostomatida) was carried out using materials collected from six localities of Korea from 1984 to 2021. Aspidelectra melolontha (Landsborough, 1852) is newly added to the bryozoan fauna of Korea, and Electra jindoica n. sp. is new to science. European A. melolontha is known to occur in brackish water of low salinity, but the species is found in New Zealand and Argentina seawater. This species is also reported as a fouling bryozoan from China and New Zealand. Electra jindoica n. sp. is distinguished by smaller zooid, larger kenozooid, and developed cryptocyst from E. asiatica Grischenko, Dick and Mawatari, 2007. With the addition of two species reported herein, six species and four genera of Electridae from Korea have been recorded: Aspidelectra melolontha, Arbopercula tenella, Conopeum hexagonum, C. reticulum, C. seurati, and Electra jindoica n. sp. Furthermore, the genera Aspidelectra and Electra are new to the Korean bryozoan fauna based on this study.

Korean Species of the Genus Taeniogonalos (Hymenoptera: Trigonalidae: Trigonalinae) with a New Record

  • Hye-Rin Lee;Danbi Yun;Tae-Ho An;Jae-Hyeon Lee;Deokseo Ku;Bong-Kyu Byun
    • Animal Systematics, Evolution and Diversity
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    • v.40 no.1
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    • pp.88-93
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    • 2024
  • In this study, we conduct a review of the genus Taeniogonalos Schulz, 1906, which belongs to the subfamily Trigonalinae (Hymenoptera: Trigonalidae) from Korea. The genus Taeniogonalos Schulz is recognized as a relatively small genus. Taeniogonalos comprises 53 described species worldwide, including nine species identified in the Eastern Palaearctic region. A total of four species have been recognized from Korea. This paper enumerates the known species in Korea, including the new record. We provide the diagnosis and photographs for the newly recorded species. Additionally, we present a key to the Korean species of Taeniogonalos Schulz, 1906.

RNF43 and ZNRF3 in Wnt Signaling - A Master Regulator at the Membrane

  • Fiona Farnhammer;Gabriele Colozza;Jihoon Kim
    • International Journal of Stem Cells
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    • v.16 no.4
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    • pp.376-384
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    • 2023
  • The Wnt 𝛽-catenin signaling pathway is a highly conserved mechanism that plays a critical role from embryonic development and adult stem cell homeostasis. However, dysregulation of the Wnt pathway has been implicated in various diseases, including cancer. Therefore, multiple layers of regulatory mechanisms tightly control the activation and suppression of the Wnt signal. The E3 ubiquitin ligases RNF43 and ZNRF3, which are known negative regulators of the Wnt pathway, are critical component of Wnt signaling regulation. These E3 ubiquitin ligases control Wnt signaling by targeting the Wnt receptor Frizzled to induce ubiquitination-mediated endo-lysosomal degradation, thus controlling the activation of the Wnt signaling pathway. We also discuss the regulatory mechanisms, interactors, and evolution of RNF43 and ZNRF3. This review article summarizes recent findings on RNF43 and ZNRF3 and their potential implications for the development of therapeutic strategies to target the Wnt signaling pathway in various diseases, including cancer.

A New Species of Arabella (Annelida, Polychaeta, Oenonidae) from Korean Waters

  • Seong Hun Kang;Yu Seok Jeong;Hyun Ki Choi;Seong Myeong Yoon
    • Animal Systematics, Evolution and Diversity
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    • v.40 no.3
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    • pp.157-166
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    • 2024
  • A new oenonid polychaete, Arabella turbidiricolor sp. nov., collected from intertidal zone along the coasts of eastern, western, and southern Korea is described. In Korea, this new species might have been confused with Arabella iricolor(Montagu, 1804), the type species of the genus, in having the following characteristics: ventralmost chaeta tapering gradually to guard, MI left robust and right gracile, MII right long, MV both with one tooth and posterior postchaetal lobe shorter than chaetae. However, A. turbidiricolor sp. nov. is readily distinguished from the latter by the following features: ventral maxillary carriers longer than or equal to dorsal, MI both distally falcate, and pygidium with two swollen pads. We provide detailed descriptions and illustrations for the new species in the present study. Also, morphological characteristics of known Arabella species are compared and discussed with a key to them.

Karyotypes, DNA Values and Nuclear Sizes of Several Scups (Teleostomi : Perciformes) (돔류(類) 몇종(種)의 염색체(染色體), DNA함량(含量)과 핵(核)의 크기에 관한 연구(硏究))

  • Kim, Dong-Soo;Jeon, Im-Gi;Lee, Jong-Kwan
    • Korean Journal of Ichthyology
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    • v.1 no.1_2
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    • pp.35-41
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    • 1989
  • An examination of the karyotypes, DNA values and nuclear sizes of three scups was undertaken as part of the study of cytogenetical evolution of order Perciformes. The chromosome number 2n=48 was the same in all three species but the numbers of chromosome arm were not identical. The distribution of genome size and nuclear volumes among species was continuous ranging from 1.287 pg and $20.78\;{\mu}m^3$ for Pagrus major down to 1.237 pg and $20.56\;{\mu}m^3$ for Acanthopagrus schlegeli. Above results indicate the possible role of pericentric inversions in the karyotypic evolution of these species.

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Effects of Soil Types on the Biodegradation of Crude Oil by Nocardia sp. H17-1

  • Yoon, Byung-Dae;Baek, Kyung-Hwa;Kim, Hee-Sik;Moon, Seong-Hoon;Lee, In-Sook;Oh, Hee-Mock
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.901-905
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    • 2004
  • The degradation and mineralization of crude oil were investigated over 50-days in three soils, loamy sand, sand, and combusted loamy, which were artificially contaminated with crude oil (50 g $kg^{-1}$) and inoculated with Nocardia sp. H17-1. The degradation efficiency of total petroleum hydrocarbon (TPH) in sand was the highest at 76% among the three soils. The TPH degradation rate constants $(k_{TPH})$ in loamy sand, sand, and combusted loamy sand were 0.027 $d^{-1}$, 0.063 $d^{-1}$, and 0.016 $d^{-1}$, respectively. In contrast, the total amount of $CO_2$ evolved was the highest at 146.1 mmol in loamy sand. The $CO_2$ evolution rate constants (k_{CO2})$ in loamy sand, sand, and combusted loamy sand were 0.057 $d^{-1}$, 0.066 $d^{-1}$, and 0.037 $d^{-1}$, respectively. Therefore, it seems that the degradation of crude oil in soils can be proportional to the soil pore space and that mineralization can be accelerated with the increase of organic substance.

An Evolution of Cellular Automata Neural Systems using DNA Coding Method (DNA 코딩방법을 이용한 셀룰라 오토마타 신경망의 진화)

  • Lee, Dong-Wook;Sim, Kwee-Bo
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.12
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    • pp.10-19
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    • 1999
  • Cellular Automata Neural Systems(CANS) are neural networks based on biological development and evolution. Each neuron of CANS has local connection and acts as a form of pulse according to the dynamics of the chaotic neuron. CANS are generated from initial cells according to the CA rule. In the previous study, to obtain the useful ability of CANS, we make the pattern of initial cells evolve. However, it is impossible to represent all solution space, so we propose an evolving method of CA rule to overcome this defect in this paper. DNA coding has the redundancy and overlapping of gene and is apt for the representation of the rule. In this paper, we show the general expression of CA rule and propose translation method from DNA code to CA rule. The effectiveness of the proposed scheme was verified by applying it to the navigation problem of autonomous mobile robot.

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Potential Industrial Applications and Evolution of Carbohydrolases and Glycansucrases

  • Kim, Do-Man;Seo, Eun-Seong;Lee, Jin-Ha;Kang, Hee-Kyoung;Cho, Jae-Young
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 2004.06a
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    • pp.215-218
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    • 2004
  • Dextrans make up a class of polysaccharides that are D-glucans of various structures with contiguous $\alpha$-1longrightarrow6 ~6 glycosidic linkages in the main chains and $\alpha$-1longrightarrow2, $\alpha$-1longrightarrow3, or $\alpha$-1longrightarrow4 branch glycosidic linkages, depending on the specificity of the particular dextransucrase. Glucansucrases that catalyze glucans synthesis from sucrose. When other carbohydrates, in addition to sucrose, are present in the enzyme digest, the enzyme transfers glucose to the carbohydrate acceptors in the secondary reaction that diverts some of the glucose from incorporation into glucan. Many carbohydrate acceptors have been recognized and the products that result are dependent on the particular enzyme and the structure of the particular acceptor. Because of these unique catalytic characteristics, various dextransucrases have many important industrial and medical uses. To improve the understanding of their action mode and extend their applications, this study describes mechanism of glucan synthesis and potential industrial uses of dextransucrases, and our recent findings on the structural, functional organization and directed evolution of the glucansucrases to offer for designing glucansucrases with improved properties.

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