Transport of lipids in insects
Many insect species are almost completely dependent on lipids for their metabolic needs, although this is usually a function of developmental stage. The primary storage organ is the fat body, which can constitute 50% of the fresh weight of the insect and also acts as the major metabolic center (anal...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Elsevier
1974-09-01
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| Series: | Journal of Lipid Research |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S002222752036764X |
| _version_ | 1818743178827661312 |
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| author | Lawrence I. Gilbert Haruo Chino |
| author_facet | Lawrence I. Gilbert Haruo Chino |
| author_sort | Lawrence I. Gilbert |
| collection | DOAJ |
| description | Many insect species are almost completely dependent on lipids for their metabolic needs, although this is usually a function of developmental stage. The primary storage organ is the fat body, which can constitute 50% of the fresh weight of the insect and also acts as the major metabolic center (analogous to the vertebrate adipose tissue and liver). Bathing the fat body (and all other tissues and organs) is the hemolymph, the main functions of which are to transport nutrient substrates to utilization sites and to deliver metabolic wastes to the excretory system.Although neutral lipids are stored as triglycerides, in times of need they appear to be endergonically released into the hemolymph as diglycerides in the majority of insects thus far studied (particularly silkmoths and locusts). Indeed, diglycerides constitute the largest neutral lipid fraction in the hemolymph of silkmoths, locusts, cockroaches, bugs, etc. In the hemolymph the diglyceride is found as a constituent of specific lipoproteins, and one specific lipoprotein class (lipoprotein I; high density lipoprotein) appears to be necessary for the transport of diglyceride from the fat body cell into the hemolymph. This particular lipoprotein is also involved in the transport of cholesterol from the gut into the hemolymph. Thus, lipoprotein I appears to be the major neutral lipid and sterol transport agent in the insects studied and, in addition, plays a regulatory role in the release of both diglycerides and sterols. Hemolymph lipoprotein II (very high density lipoprotein) may be important in providing protein and lipid to the insect ovary during oogenesis.Ecdysone, the polyhydroxy steroidal insect molting hormone, is probably carried “free” in the hemolymph, although reports exist of specific hemolymph-binding proteins in some species. The other major insect growth hormone, juvenile hormone, is transported by hemolymph lipoproteins in silkmoths and locusts and by a lower molecular weight hemolymph protein in the tobacco hornworm. |
| first_indexed | 2024-12-18T02:24:17Z |
| format | Article |
| id | doaj.art-5e9a9475f02f404fa571eabaa5d48cd1 |
| institution | Directory Open Access Journal |
| issn | 0022-2275 |
| language | English |
| last_indexed | 2024-12-18T02:24:17Z |
| publishDate | 1974-09-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Lipid Research |
| spelling | doaj.art-5e9a9475f02f404fa571eabaa5d48cd12022-12-21T21:24:06ZengElsevierJournal of Lipid Research0022-22751974-09-01155439456Transport of lipids in insectsLawrence I. Gilbert0Haruo Chino1Department of Biological Sciences, Northwestern University, Evanston, Illinois 60201, and; Biochemistry Section, The Institute of Low Temperature Science, Hokkaido University, Sapporo, JapanDepartment of Biological Sciences, Northwestern University, Evanston, Illinois 60201, and; Biochemistry Section, The Institute of Low Temperature Science, Hokkaido University, Sapporo, JapanMany insect species are almost completely dependent on lipids for their metabolic needs, although this is usually a function of developmental stage. The primary storage organ is the fat body, which can constitute 50% of the fresh weight of the insect and also acts as the major metabolic center (analogous to the vertebrate adipose tissue and liver). Bathing the fat body (and all other tissues and organs) is the hemolymph, the main functions of which are to transport nutrient substrates to utilization sites and to deliver metabolic wastes to the excretory system.Although neutral lipids are stored as triglycerides, in times of need they appear to be endergonically released into the hemolymph as diglycerides in the majority of insects thus far studied (particularly silkmoths and locusts). Indeed, diglycerides constitute the largest neutral lipid fraction in the hemolymph of silkmoths, locusts, cockroaches, bugs, etc. In the hemolymph the diglyceride is found as a constituent of specific lipoproteins, and one specific lipoprotein class (lipoprotein I; high density lipoprotein) appears to be necessary for the transport of diglyceride from the fat body cell into the hemolymph. This particular lipoprotein is also involved in the transport of cholesterol from the gut into the hemolymph. Thus, lipoprotein I appears to be the major neutral lipid and sterol transport agent in the insects studied and, in addition, plays a regulatory role in the release of both diglycerides and sterols. Hemolymph lipoprotein II (very high density lipoprotein) may be important in providing protein and lipid to the insect ovary during oogenesis.Ecdysone, the polyhydroxy steroidal insect molting hormone, is probably carried “free” in the hemolymph, although reports exist of specific hemolymph-binding proteins in some species. The other major insect growth hormone, juvenile hormone, is transported by hemolymph lipoproteins in silkmoths and locusts and by a lower molecular weight hemolymph protein in the tobacco hornworm.http://www.sciencedirect.com/science/article/pii/S002222752036764Xhormoneecdysonejuvenile hormonesilkmothdiglyceridelipoprotein |
| spellingShingle | Lawrence I. Gilbert Haruo Chino Transport of lipids in insects Journal of Lipid Research hormone ecdysone juvenile hormone silkmoth diglyceride lipoprotein |
| title | Transport of lipids in insects |
| title_full | Transport of lipids in insects |
| title_fullStr | Transport of lipids in insects |
| title_full_unstemmed | Transport of lipids in insects |
| title_short | Transport of lipids in insects |
| title_sort | transport of lipids in insects |
| topic | hormone ecdysone juvenile hormone silkmoth diglyceride lipoprotein |
| url | http://www.sciencedirect.com/science/article/pii/S002222752036764X |
| work_keys_str_mv | AT lawrenceigilbert transportoflipidsininsects AT haruochino transportoflipidsininsects |