Cell Constitution 



45 



Bricka ('49) and partly of the so-called 

 "endoplasmic reticulum" which Porter ('53) 

 and Porter and Kallman ('52) regard as a 

 system of RNA-protein-containing structures 

 which may appear canalicular or reticular 

 and which may be concerned with synthetic 

 processes in the cell. A somewhat different 

 description of the same component has been 

 given by Sjostrand and Rhodin ('53). This 

 class of cytoplasmic organelles is probably of 

 considerable functional importance and 

 worthy of fvirther detailed study. 



SUPERNATE 



The supernate which remains after cen- 

 trifugal removal of the small granule frac- 

 tion contains chiefly globular proteins (Sorof 

 et al., '51a, b, c; Gjessing et al., '51), organic 

 and inorganic compounds of relatively low 

 molecular weight, "soluble" enzymes, some 

 RNA, nucleotides and the like. 



LIPOCHONDRIA (GOLGI SYSTEM) 



Despite the enormous literature (over 2000 

 papers) written during the last half century 

 on the Golgi apparatus, "we know very little 

 and ovir hypotheses are pure guesses," to 

 quote Bensley ('51). After reviewing the 

 literature, Palade and Claude ('49a, b) con- 

 clude that the Golgi system as seen in cyto- 

 logical preparations is an artifact produced 

 by the action of the alcohol in the fixative 

 upon pre-existing highly refringent droplets 

 which stain with Sudan black and have an 

 affinity for neutral red; the more slowly dif- 

 fusing osmium tetroxide then fixes these arti- 

 facts in the form characteristic of the Golgi 

 apparatus. Structures closely resembling 

 Golgi apparatus were produced by the action 

 of fixatives on lipid-containing fractions of 

 cells. 



Palade and Claude ignore the evidence 

 that the Golgi material can be seen in the 

 living cell. According to Baker ('49), "the 

 Golgi bodies are the most evident objects in 

 the cell," where they appear as spheroids 

 when viewed with phase contrast. Bensley 

 ('51), Gatenby and Moussa ('51) and others 

 favor the view that the "apparatus" pre- 

 exists in the cell as vesicles and canals simi- 

 lar to the structures seen in fixed prepara- 

 tions. 



The evidence seems to the present writer 

 to indicate that the Golgi bodies represent a 

 pleomorphic system which pre-exists in the 

 cytoplasm and whose colloidal organization 

 is sensitive to alterations of the environment. 



particularly to acids and organic solvents. 

 Although little is really known about their 

 chemical composition (Sosa, '48) there seems 

 little doubt that lipids are an important com- 

 ponent and may be primarily responsible 

 for the pleomorphism. 



It may be desirable, therefore, to adopt 

 Baker's ('50) suggestion to drop the name 

 Golgi apparatus (since this may indeed be 

 an artifact) and refer to the system as 

 "lipochondria." Adopting this relatively non- 

 commital name may restore respectability to 

 a cellular system which is almost certainly 

 an important protoplasmic constituent and 

 which, because of colloidal sensitivity, has 

 suffered much uncritical abuse. 



The evidence in the cytological literature 

 that lipochondria are intimately associated 

 with the process of secretion, though circum- 

 stantial, is perhaps as good as that which, in 

 the same literature, associated mitochondria 

 with respiration (which later biochemical 

 evidence proved to be correct). To what ex- 

 tent the lipochondrial system will prove to 

 be multicomponent, with "internal and ex- 

 ternal" components, remains to be seen. The 

 author leans to the view that a portion of 

 the instability and of the difficulty of obtain- 

 ing the material as particulates from frag- 

 mented cells (see Worley, '51) may be due 

 to the fact that certain of the components 

 exist in the smectic paracrystalline state (a 

 view not inconsistent with the meager polar- 

 ized light data available). If so, the pleo- 

 morphism, ease of solvation and sensitivity 

 to alterations in the chemical environment 

 would be expected. 



Fairly substantial evidence points to the 

 possibility that ascorbic acid and phospha- 

 tase occur in lipochondria. Gersh ('49), ap- 

 plying the Hotchkiss reaction to frozen-dried 

 material, concluded that the material which 

 reacts positively is a glycoprotein which may 

 provide "a suitable frame-work for the or- 

 derly arrangement of enzymes and other 

 activities." This must be regarded as pure 

 speculation at the present time. 



The determination of the composition and 

 function of lipochondria has lagged behind 

 that for mitochondria for the reason that the 

 subject is very much more complex and diffi- 

 cult. However, especially if the material is 

 involved in the vital process of secretion, 

 the problem is all the more challenging and 

 worthy of a renewed vigorous attack in- 

 volving the chemical and enzymatic as well 

 as the morphological approach. Quite pos- 

 sibly progress would be accelerated by the 

 exploitation of the most favorable source of 



