Gene silencing reveals a crucial role for anti-lipopolysaccharide factors from Penaeus monodon in the protection against microbial infections.
Anti-lipopolysaccharide factors (ALFs) are antimicrobial peptides previously identified in various crustaceans. Out of five isoforms identified in Penaeus monodon, ALFPm3 is the best characterized, exhibits antibacterial and antifungal activities and can protect the shrimp from viral infections. Herein, the most recent identified ALFPm, called ALFPm6, is characterized for its potential role in the shrimp's immunity. RNA interference-mediated gene silencing was used to study the function of ALFPm6 in comparison to ALFPm3. Knockdown of ALFPm3 gene led to rapid death with a cumulative shrimp mortality of 86% within 7 days, accompanied by a 12- and 50-fold higher bacterial count after 2 days in the haemolymph and hepatopancreas, respectively, compared to the control shrimp injected with GFP dsRNA. In contrast, gene silencing of ALFPm6 alone had no effect on the shrimp mortality, but led to a significant increase in the cumulative mortality and a faster mortality rate following Vibrio harveyi and white spot syndrome virus (WSSV) infections, respectively. These results support the roles of ALFPm6 and ALFPm3 in the protection of shrimp against microbial infections.
Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand.
Sirikwan
S
Ponprateep
Sirinit
S
Tharntada
Kunlaya
K
Somboonwiwat
Anchalee
A
Tassanakajon
D000818:Animals; D060829:Arthropod Proteins / Q000235:genetics* / Q000378:metabolism*; D058491:Bacterial Load; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D020868:Gene Silencing; D006458:Hemolymph / Q000382:microbiology; D043143:Hepatopancreas / Q000382:microbiology; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000382:microbiology*; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis; D014733:Vibrio / Q000276:immunology / Q000502:physiology*
D060829:Arthropod Proteins