Training Teaching Marine Programs

Research

Publications Students Contact
Training and Awards
  • BA Biology 1973 California State College, Sonoma.

  • MA Biology 1975 California State College, Sonoma - with Dr. Colin Hermans (Interstitial Fauna)

  • PhD Zoology 1978 UC Berkeley - with Dr. Richard Eakin (Invertebrate photoreceptors; ciliary locomotion)

  • PostDoct UC Riverside - with Dr. Prudence Talbot (Mammalian Ovulation)

  • Occidental College since 1980

  • Loftsgordon Award for Excellence in Teaching 1984

Teaching

Bio 115: Introductory Zoology

Bio 323: Histology

Bio 344: Comparative Invertebrate Morphology and Physiology

 

Director of Marine Programs at Oxy and Summer Oceanology Program
for High School Seniors

Pictures Below:
  • Left: Collecting shrimp by otter trawl.
  • Middle:Taking a blood sample from Sicyonia ingentis, our main subject.
  • Right: Analyzing samples with our Zeiss EM 109 TEM.
 

Large granule hemocyte and granules from S. ingentis.

FITC-labeled WGA stained hemocytes from S. ingentis. Large granule cell is positive and hyaline cell is negative.
Research
Work in my lab (with primarily undergraduates) focuses on the morphological examination of mechanisms by which crustaceans (especially shrimp) fight infection and disease. We have developed a classification scheme for circulating blood cells based on morphology, cytochemistry and function. Hyaline cells lyse to initiate coagulation of the hemolymph thereby preventing dissemination of pathogens throughout the body. Granulocytes, both small and large granule varieties, phagocytose and encapsulate foreign materials and release chemicals such as phenoloxidase. Nodules composed of foreign materials and blood cells form rapidly in the blood and are filtered out primarily in the narrow vessels of the gills. We have also examined the midgut trunk and associated peritrophic membrane as possible barriers to the penetration of ingested microbes into the body.

     Current research is also looking at the structure of the digestive tract of the Giant Keyhole limpet, Megathura crenulata. The respiratory pigment (hemocyanin) in this gastopod shows promise in the treatment of medical conditions including cancer. We are interested in the structure and function of the various regions of the gut with regard to suggesting better diets for the culture of these limpets, identifying potential pathogens, and also locating high concentrations of rhogocytes which may produce the keyhole limpet hemocyanin (KLH)

 
List of Publications: most recent at the bottom (*indicates OXY Student Co-Author)
Fine structure and classification of shrimp hemocytes. 1985 with B Graves*.

Structure of hematopoietic nodules in the ridgeback prawn, Sicyonia ingentis: light and electron microscope observations. 1987 with JE Hose and JJ Kim* (Later work showed the organ to be lymphoid organ and not hematopoietic tissue!).

Cytochemical features of shrimp hemocytes. 1987 with JE Hose, VA Nguyen*, J Lucus* and T Rosenstein*

Morphology and hemocyte lysis and clotting in the Ridgeback prawn, Sicyonia ingentis. 1989 with S. Omori* and JE Hose.

Defense functions of granulocytes in the ridgeback prawn, Sicyonia ingentis. 1989 with JE Hose.

Morphological comparison of major arteries in ridgeback prawn, Sicyonia ingentis. 1989 with C Corzine* and JE Hose.

A decapod hemocyte classification scheme integrating morphology, cytochemistry and function. 1990 with JE Hose and A Gerard*

Patterns of hemocyte production and release throughout the molt cycle in the Peneaeid shrimp, Sicyonia ingentis. 1992 with JE Hose, S Tiu* and N McKrell*

Vascular elements and blood (hemolymph) 1992 with JE Hose.

Clearance of bacteria injected into hemolymph of the penaeid shrimp, Sicyonia ingentis 1993 with C Poole, C Poole*, JE Hose, M Arias*, L Reynolds, N McKrell.

Organization of hematopoietic tissue in the intermolt lobster Homarus americanus. 1993 with JE Hose, M Choi*, R Provost*, G Omori*, N McKrell* and G Lam*.

Clearance of bacteria injected into hemolymph of the Ridgeback prawn: Sicyonia ingentis (Crustacea, Decapoda): Role of hematopoietic tissue. 1996 with JE Hose, G Minka* and S Rosenberg*.

In vitro nodule formation in the ridgeback prawn Sicyonia ingentis and the American lobster, Homarus americanus. 1998 with J Kay*, D Poole and C Poole*.
 

Rexamination of hemocytes in Brine shrimp (Crustacea, Branchiopoda)1999 with HM J Lin* and C Luc* 

Photobehavior of the Harpacticoid copepod Tigriopus californicus and the fine structure of its nauplius eye. 2000 with C Speekmann* and S Beidler*.

Elimination of sequestered materials from the gills of decapod crustaceans. 2000 with M Qunitero*, M Quigley* and H Khosrovian*.

N-acetyl-D-glucosamine in crustacean hemocytes; possible functions and usefullness in hemocyte classification. 2003 with C Castro*, N Moy* and N Rubin*.
 

Localization and roles of coagulogen and transglutaminase in hemolymph coagulation in decapod crustaceans.
 

Morphology of the midgut trunk in the Penaeid shrimp, Sicyonia ingentis, highlighting novel nuclear pore particles and fixed hemocytes. 2003 with A Chiu*.

Vibrio parahaemolyticus and V. Harveyi cause detachment of the epithelium from the midgut trunk of the penaeid shrimp Sicyonia ingentis. 2004 with N. Rubin* and E. Swanson*. 

The three-dimensional detection of microvasculatory bed in the brain of white rat Rattus norvegicus by a Ca2+-ATPase method. 2005 with Amaiak Chilingaryan* and Amayak M. Chilingaryan

Peritrophic membrane of the penaeid shrimp Sicyonia ingentis: structure, formation and permeability. 2006 with Rebecca Simcox*, Aivan Nguyen*, and Amaiak Chilingaryian*.

Structure and function of hemocytes in two marine gastropods Aplysia californica and Megathura crenulata. 2007 with Christopher Oakes*, Heather Tousignant*, Heather Crabtree*, and Rachel Yamakawa*


 

 
Recent Student Projects
  • Shannon Sullivan: Identification of digestive enzymes in specific regions of the gut of the giant keyhole limpet, Megathura crenulata.

  • David James and Mike Salisbury: Morphology of the proboscis in the cone snail, Conus cattus.

  • Tracy Bessette, Kate Vumbaco, Alanna Martin, Renae Cotero, Julianna Howland, and Philip Allan: Morphology of digestive tract in the giant keyhole limpet, Megathura crenulata.

  • Heather Tousignant, Heather Crabtree, Chris Oakes and Rachel Yamakawa: Characterization of hemocytes in Aplysia californica.

  • Amaiak Chilingaryan: Properties of the midgut trunk and peritrophic membrane in penaeid shrimp.

  • Christina Bracamonte: Structure, chemical composition, and permeability of the peritrophic membrane in Sicyonia ingentis.

  • Alice Chiu: Morphology of the midgut trunk in penaeid shrimp.

  • Nicole Rubin and Erica Swanson: Effect of Vibrio on the midgut trunk of the ridgeback prawn.

  • Becky Simcox, Stephanie Olson, Aivan Nguyen: Structure and formation of the peritrophic membrane in Sicyonia ingentis.

  • Erin Amirian: Chemical composition of the peritrophic membrane in Sicyonia ingentis.

  • Christa Speekmann: Ultrastructure of the nauplius eye in the copepod, Tigriopus californicus.

Contact Information

Department of Biology Room 108
Occidental College,
Los Angeles, CA 90041

(323) 259-2890 voice
(323) 341-4974 FAX
(323) 259-2697 department
gmartin@oxy.edu

Last Updated: Matthew Liter 04/23/04