Coté G G, Brody S
Department of Biology, University of California, San Diego, La Jolla 92093.
Biochim Biophys Acta. 1987 Nov 2;904(1):131-9. doi: 10.1016/0005-2736(87)90094-0.
The fatty acid compositions of the phospholipids of Neurospora crassa mutants with altered periods were determined to test the possibility that some of these mutants might have altered membrane composition. In liquid shaker culture in constant light the bd (band) strain, which has a normal period (21.6 h), exhibited a growth-dependent increase in linoleic acid content and a decrease in linolenic acid content during early log phase growth. By late log phase, fatty acid composition was essentially constant. The phospholipid fatty acid compositions of bd strains containing mutations at the frq (frequency) and chr (chrono) loci were indistinguishable from that of the bd strain under the conditions used. However, a bd strain containing a mutation at the prd-1 (period) locus, as well as prd-1 segregants from a cross of this strain to a bd strain, had altered patterns of growth-dependent fatty acid composition; linoleic and linolenic acid contents changed more slow than in the bd strain and continued to change throughout growth. In addition, the fatty acid composition of a bd prd-1 strain on solid medium differed from that of the bd strain. It is proposed that the prd-1 mutation leads to altered membrane homeostasis, which in turn affects circadian rhythmicity because some or all components of the rhythm-generating system are membrane-localized.
测定了周期改变的粗糙脉孢菌突变体磷脂的脂肪酸组成，以检验这些突变体中某些可能具有改变的膜组成的可能性。在持续光照下的液体摇瓶培养中，具有正常周期（21.6小时）的bd（带）菌株在对数生长早期表现出亚油酸含量随生长而增加，亚麻酸含量降低。到对数生长后期，脂肪酸组成基本恒定。在所使用的条件下，在frq（频率）和chr（生物钟）位点含有突变的bd菌株的磷脂脂肪酸组成与bd菌株无法区分。然而，在prd - 1（周期）位点含有突变的bd菌株以及该菌株与bd菌株杂交产生的prd - 1分离株，其依赖生长的脂肪酸组成模式发生了改变；亚油酸和亚麻酸含量的变化比bd菌株更缓慢，并且在整个生长过程中持续变化。此外，bd prd - 1菌株在固体培养基上的脂肪酸组成与bd菌株不同。有人提出，prd - 1突变导致膜稳态改变，进而影响昼夜节律，因为节律产生系统的某些或所有成分都位于膜上。
