Genomic organization of the cytosolic manganese superoxide dismutase gene from the Pacific white shrimp, Litopenaeus vannamei, and its response to thermal stress.

Cytosolic manganese superoxide dismutase (cMnSOD) is an important antioxidant enzyme which catalyzes the conversion of superoxides to oxygen and hydrogen peroxide in several organisms. In the Pacific white shrimp, Litopenaeus vannamei, three cMnSOD genes (LvcMnSOD1-3) have previously been characterized. Here, the genomic structure of LvcMnSOD2 and its mRNA expression in response to thermal stress was examined.

Two plasmolipins from the black tiger shrimp, Penaeus monodon and their response to virus pathogens.

Two isoforms of plasmolipin were initially identified from the black tiger shrimp (Penaeus monodon) EST database and completed using 50 RACE to reveal complete cDNAs of 558 bp (PmPLP1) and 537 bp(PmPLP2) with 87% nucleotide sequence identity. The deduced amino acid sequences contained four-transmembrane domains and showed the highest amino acid identity (49% and 51%, respectively) to the honey bee (Apis mellifera) chemokine-like factor (CKLF), with a very similar hydrophobic pattern to other plasmolipins. Transcripts of PmPLP1 and PmPLP2 were observed in all tested shrimp tissues with the highest expression levels in the gill and epipodite for PmPLP1 and in the hemocytes and antennal gland for PmPLP2.

Expression analysis and response of Penaeus monodon 14-3-3 genes to salinity stress.

Two isoforms of 14-3-3 protein, namely 14-3-3A and 14-3-3B, from the shrimp Penaeus monodon were investigated for their potential role in adaptation to salinity stress. Transcripts of 14-3-3A were found in various shrimp tissues whilst expression of 14-3-3B transcripts was more specific being observed in the osmoregulatory tissues, that is in the gills and epipodites. In shrimp gills, the 14-3-3A transcript levels slightly changed after transfer of the shrimp from 3 to 25 or to 40 ppt.

A cDNA microarray approach for analyzing transcriptional changes in Penaeus monodon after infection by pathogens.

A cDNA microarray comprised of 9990 different ESTs obtained from the Penaeus monodon EST project (http://pmonodon.biotec.or.

Identification of genes expressed in response to yellow head virus infection in the black tiger shrimp, Penaeus monodon, by suppression subtractive hybridization.

Suppression subtractive hybridization (SSH) was employed to identify yellow head virus (YHV)-responsive genes from the hemocytes of the black tiger shrimp, Penaeus monodon. Two SSH cDNA libraries were constructed to identify viral responsive genes in the early (24I) and late (48/72I) phases of YHV infection. From 240 randomly selected clones from each library, 155 and 30 non-redundant transcripts were obtained for the early and late libraries, respectively.

Gene expression and activity of carbonic anhydrase in salinity stressed Penaeus monodon.

Carbonic anhydrase (CA) was identified by differential display PCR analysis as one of the differentially expressed genes in the gills of low salinity stressed (transferred from 25 to 3 ppt) Penaeusmonodon. To further characterize the role of CA in the regulation of salinity stress, the cDNA sequence of P.monodon carbonic anhydrase (PmCA) was attained by rapid amplification of cDNA ends and found to have a total length of 1194 bp.

Differentially expressed genes in Penaeus monodon hemocytes following infection with yellow head virus.

A cDNA microarray composed of 2,028 different ESTs from two shrimp species, Penaeus monodon and Masupenaeus japonicus, was employed to identify yellow head virus (YHV)-responsive genes in hemocytes of P. monodon. A total of 105 differentially expressed genes were identified and grouped into five different clusters according to their expression patterns.

Abundantly expressed transcripts in the lymphoid organ of the black tiger shrimp, Penaeus monodon, and their implication in immune function.

The lymphoid organ of penaeid shrimps is proposed to play an important role in the innate immune system. To investigate the potential immune function of the lymphoid organ, we analyzed the expressed genes from the lymphoid organ of normal and Vibrio harveyi-infected Penaeus monodon using an expressed sequence tag (EST) approach. Sequence analysis of the EST clones derived from the two lymphoid organ cDNA libraries (408 clones from the normal and 625 clones from the infected libraries), revealed a high redundancy of specific transcripts.

Penaeus monodon gene discovery project: the generation of an EST collection and establishment of a database.

A large-scale expressed sequence tag (EST) sequencing project was undertaken for the purpose of gene discovery in the black tiger shrimp Penaeus monodon. Initially, 15 cDNA libraries were constructed from different tissues (eyestalk, hepatopancrease, haematopoietic tissue, haemocyte, lymphoid organ, and ovary) of shrimp, reared under normal or stress conditions, to identify tissue-specific genes and genes responding to infection and heat stress. A total of 10,100 clones were analyzed by single-pass sequencing from the 5' end.