foodsystFood systemsПищевые системы2618-97712618-7272Федеральный научный центр пищевых систем им. В.М. Горбатова РАН10.21323/2618-9771-2023-6-3-283-287foodsyst-296Research ArticleСтатьиStructural characteristics of the bovine leukemia virus genome: A mini reviewСтруктурные характеристики генома вируса лейкоза крупного рогатого скота: мини-обзорhttps://orcid.org/0000-0001-7852-3790ФоменкоО. Ю.FomenkoO. Yu.

Фоменко Олег Юрьевич — кандидат биологических наук, старший научный сотрудник, Центральная лаборатория микробиологии

115093, Москва, ул. Люсиновская, 35/7

Тел.: +7–904–211–01–75

Oleg Yu.  Fomenko, Candidate of Biological Sciences, Senior Researcher, Central Laboratory of Microbiology

35/7, Lyusinovskaya str., 115093, Moscow

Tel.: +7–904–211–01–75

o_fomenko@vnimi.orgВсероссийский научно-исследовательский институт молочной промышленностиРоссияAll-Russian Dairy Research InstituteRussian Federation20231210202363283287Copyright © Fomenko O.Y., 20232023Фоменко О.Ю.Fomenko O.Y.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.fsjour.com/jour/article/view/296

Enzootic bovine leukemia is an infectious disease with a chronic course caused by an RNA‑containing virus of the genus Deltaretrovirus. Despite the implementation of various programs for the elimination of leukemia, the disease is still widespread on the planet and continues to cause significant economic damage. A large proportion of BLV‑infected cattle remain to be asymptomatic carriers of the virus, which complicates diagnosis and contributes to the spread of the disease in the herd. The structure of the BLV genome is generally typical of retroviruses. It consists of genes encoding structural proteins, viral enzymes and regulatory elements flanked on both sides by identical long terminal repeats. The enzyme and structural protein coding genes (gag, pro, pol, and env) play a crucial role in the life cycle of the virus, influencing its infectivity and virion production. The tax and rex regulatory genes regulate viral transcription, export of transcripts from the nucleus to the cytoplasm, and disease progression. The increase in the number of copies of proviral DNA occurs mainly not due to the functioning of the virus reverse transcriptase, but because of clonal reproduction of the affected subpopulations of B‑cells, mainly CD5+ IgM+. This feature provides increased genetic stability of the BLV virus. These properties of the viral genome allow the development of a variety of PCR test systems. The widespread implementation of such systems enables the detection of carriers of the disease at early stages, which should contribute to the effective implementation of national programs to eradicate bovine leukemia.

Энзоотический лейкоз крупного рогатого скота — это инфекционное заболевание с хроническим течением, вызываемое РНК-содержащим вирусом из рода Deltaretrovirus. Несмотря на внедрение различных программ по ликвидации лейкоза, заболевание остается широко распространенным на планете и продолжает наносить значительный экономический ущерб. Большинство инфицированных вирусом BLV животных остаются бессимптомными носителями вируса, что осложняет постановку диагноза и способствует распространению заболевания в стаде. Структура генома вируса BLV в целом типична для представителей ретровирусов. В его состав входят гены, кодирующие структурные белки, вирусные ферменты и регуляторные элементы, фланкированные с обеих сторон идентичными длинными концевыми повторами. Гены, кодирующие ферменты и структурные белки (gag, pro, pol и env), играют важнейшую роль в жизненном цикле вируса, оказывая влияние на его инфекционность и производство вирионов. Регуляторные гены tax и rex обеспечивают регуляцию вирусной транскрипции, экспорт транскриптов из ядра в цитоплазму и прогрессирование заболевания. При этом увеличение числа копий провирусной ДНК происходит в основном не за счёт функционирования обратной транскриптазы вируса, а посредством клонального размножения пораженных субпопуляций B-клеток, преимущественно CD5+ IgM+. Данная особенность обеспечивает повышенную генетическую стабильность вируса BLV. Эти свойства вирусного генома позволяют разрабатывать разнообразные ПЦР-тест системы, широкое внедрение которых позволяет выявлять носителей болезни на ранних стадиях, что должно способствовать эффективной реализации национальных программ искоренения лейкоза крупного рогатого скота.

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The authors declare that there are no conflicts of interest present.